NREL is a national laboratory of the U.S. Department of Energy, Office of Energy 

Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

Contract No. DE-AC36-08GO28308

Feasibility Study of Economics 

and Performance of Solar 

Photovoltaics at the 

Refuse Hideaway Landfill in 

Middleton, Wisconsin

A Study Prepared in Partnership with the 

Environmental Protection Agency for the 

RE-Powering America’s Land Initiative: 

Siting Renewable Energy on Potentially 

Contaminated Land and Mine Sites 

James Salasovich and Gail Mosey

Technical Report

NREL/TP-6A20-49846

August 2011
NREL is a national laboratory of the U.S. Department of Energy, Office of Energy 

Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

National Renewable Energy Laboratory

1617 Cole Boulevard

Golden, Colorado 80401

303-275-3000 • www.nrel.gov

Contract No. DE-AC36-08GO28308

Feasibility Study of Economics 

and Performance of Solar 

Photovoltaics at the 

Refuse Hideaway Landfill in 

Middleton, Wisconsin

A Study Prepared in Partnership with the 

Environmental Protection Agency for the 

RE-Powering America’s Land Initiative: 

Siting Renewable Energy on Potentially 

Contaminated Land and Mine Sites

James Salasovich and Gail Mosey

Prepared under Task No. WFD4.1000

Technical Report

NREL/TP-6A20-49846

August 2011
NOTICE

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express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of 

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iii

Acknowledgments

We would like to thank Hank Kuehling, Department of Natural Resources, and John Fagiolo, 

EPA, for assisting with the site visit of the Refuse Hideaway Landfill.
iv

Executive Summary

The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering 

America’s Land initiative, selected the Refuse Hideaway Landfill in Middleton, Wisconsin, for a 

feasibility study of renewable energy production. Citizens of Middleton, city planners, and site 

managers are interested in redevelopment uses for landfills in Wisconsin that are particularly 

well suited for solar photovoltaic (PV) installation. The purpose of this report is to assess the 

Refuse Hideaway Landfill for possible PV installation and estimate the cost, performance, and 

site impacts of three different PV options: crystalline silicon (fixed tilt), crystalline silicon 

(single-axis tracking), and thin film (fixed tilt). Each option represents a standalone system that 

can be sized to use an entire available site area. In addition, the report outlines financing options 

that could assist in the implementation of a system. Landfill gas is another possible renewable 

energy option for the landfill in Middleton. Landfill gas is briefly addressed in this feasibility 

study, but PV is the main focus. 

The feasibility of PV systems installed on landfills is highly impacted by the available area for an 

array, solar resource, operating status, landfill cap status, distance to transmission lines, and 

distance to major roads. The Refuse Hideaway Landfill is suitable in area to have a large-scale 

PV system, and the solar resource in Middleton, Wisconsin, is appropriate. The findings from 

this report can also be applied to other landfills in Wisconsin. 

The economics of the potential systems were analyzed using the current Madison Gas and 

Electric (MG&E) electric rate of $0.1333/kWh and incentives offered by the State of Wisconsin

and by the serving utility, MG&E. State incentives are currently not offered for commercial solar 

power systems in Wisconsin. 

A 10 kW PV system was installed at the Refuse Hideaway Landfill in 2010, and this system 

occupies approximately 1% of the available land that is feasible for a PV system at the site. This 

PV system produces approximately 25% of the electricity required to run the pumps and fans 

related to the remediation system at the site. The entire site does not need to be developed; 

increasing the PV capacity as funds become available is a viable approach. Calculations for this 

analysis reflect the solar potential if the total feasible area is used. It is also assumed that the 30% 

federal tax credit incentive would be captured for the system.

The economics of a potential PV system on the Refuse Hideaway Landfill depend greatly on the 

cost of electricity. Currently, MG&E has an average electric rate of $0.1333/kWh. Based on past 

electric rate increases in Wisconsin, this rate could increase to $0.15/kWh or higher in a 

relatively short amount of time. Table ES-1 summarizes the system performance and economics 

of potential systems that would use all available areas that were surveyed at the Refuse 

Hideaway Landfill. The table shows the annual energy output from the system along with the 

number of average American households that could be powered off of such a system. The table 

lists results assuming the current electric rate of $0.1333/kWh and shows results assuming a 

hypothetical rate increase to $0.15/kWh. In the coming years, increasing electrical rates and 

increased necessity for clean power will continue to improve the feasibility of implementing 

solar PV systems at landfill sites. 
v

Table ES-1. Refuse Hideaway PV System Performance and Economics by System Type, Including Job Creation Estimatesa

Annual Cost Savings 

($/year)

Payback Period

(years)

PV 

System 

Size

(kW)

Annual 

Output

(kWh/year)

Number 

of Houses 

Powered b

With 

Current 

Rate

($0.13/kWh)

With Rate 

Increase

($0.15/kWh)

Annual 

O&M 

($/year)

System Cost 

with 

Incentives 

($)

With 

Incentives & 

Current 

Rate

With 

Incentives & 

Hypothetical 

Rate Increase

Jobs c

Created

(job-yr)

Jobs d

Sustained

(job-yr)

Crystalline Silicon (Fixed Tilt at 43.1o)

1,350 1,661,850 150 $221,525 $249,278 $10,328 $4,252,500 20 18 66 0.11

Crystalline Silicon (Single-Axis Tracking)

1,100 1,549,477 140 $206,545 $232,422 $23,100 $4,620,000 25 22 72 0.25

Thin Film (Fixed Tilt at 43.1o)

550 677,050 61 $90,251 $101,558 $3,647 $1,501,500 17 15 23 0.04 a Data assume a maximum usable area of all feasible areas of the Refuse Hideaway Landfill of 378,384 ft2

. b Number of average American households that could hypothetically be powered by the PV system assuming 11,040 kWh/year/household.1

c Job-years created as a result of project capital investment including direct, indirect, and induced jobs. d Jobs (direct, indirect, and induced) sustained as a result of operations and maintenance (O&M) of the system.

 1 U.S. Energy Information Administration. http://www.eia.doe.gov/ask/electricity_faqs.asp#electricity_use_home. Accessed November 2, 2010.
vi 

Table of Contents 

List of Figures ........................................................................................................................................... vii

List of Tables ............................................................................................................................................. vii

1 Study Location ...................................................................................................................................... 1

2 PV Systems ........................................................................................................................................... 3

2.1 Types of PV Systems ...........................................................................................................4 

2.2 PV System Components ......................................................................................................5 

2.3 Operation and Maintenance .................................................................................................6 

2.4 PV Size and Performance ....................................................................................................7 

3 PV Site Location ................................................................................................................................... 8 

3.1 Refuse Hideaway Landfill PV System ................................................................................8

4 Economics and Performance ............................................................................................................ 14

4.1 Assumptions and Input Data for Analysis .........................................................................14 

4.2 Incentives and Financing Opportunities ............................................................................14 

4.3 Job Creation .......................................................................................................................16 

5 Potential Rate Increases .................................................................................................................... 17

6 Conclusions and Recommendations ............................................................................................... 18

Appendix A. Assumptions for Calculations ........................................................................................... 19

Appendix B. Renewable Energy Incentives ........................................................................................... 21
vii

List of Figures

Figure 1. Major components of grid-connected PV system ........................................................... 3

Figure 2. Views of the feasible area for PV at the Refuse Hideaway Landfill............................... 8

Figure 3. Sharp PV module nameplate ........................................................................................... 9

Figure 4. Ballasted PV system at the Refuse Hideaway Landfill................................................. 10

Figure 5. View of the 10 kW ballasted PV system currently at the Refuse Hideaway Landfill... 10

Figure 6. Electrical tie-in point for the PV system at the Refuse Hideaway Landfill .................. 11

Figure 7. Inverter used in the PV system at the Refuse Hideaway Landfill................................. 11

Figure 8. Aerial view of the feasible area (orange) for PV at the Refuse Hideaway Landfill...... 12

List of Tables

Table ES-1. Refuse Hideaway PV System Performance and Economics by System Type, 

Including Job Creation Estimates ....................................................................................... v

Table 1. Energy Density by Panel and System for Ground-Mounted PV ...................................... 4

Table 2. Energy Density by Panel Type for Roof-Mounted PV..................................................... 5

Table 3. Refuse Hideaway Landfill PV System Performance and Economics by System Type . 13

Table 4. Estimated Job Creation by PV System Type .................................................................. 16

Table 5. PV System Performance and Economics with a Hypothetical Rate Increase to 

$0.15/kWh......................................................................................................................... 17

Table A-1. Calculation Assumptions for Ground-Mounted PV Systems at the Refuse Hideaway 

Landfill Using Current Electric Rate of $0.1333/kWh..................................................... 19

Table A-2. Calculation Assumptions for Ground-Mounted PV Systems at the Refuse Hideaway 

Landfill Using Hypothetical Electric Rate of $0.15/kWh ................................................ 19

Table A-3. Other Assumptions, Including Assumptions for Costs and System Types................ 20

Table B-1. Redevelopment and Renewable Energy Incentives and Financing Tools.................. 21

Table B-2. Renewable Energy Development Incentives and Financing Tools Applicable to PV 22

Table B-3. State Rebates for Commercial-Sector PV Projects..................................................... 23

Table B-4. State Tax Credits for Commercial-Sector PV Projects............................................... 27

Table B-5. U.S. Department of Energy Brightfields Program Grants.......................................... 33

Table B-6. State Policy and Incentive Comparisons: Massachusetts, North Carolina, and 

Colorado............................................................................................................................ 35

Table B-7. Key Policy Comparison for Subject States................................................................. 37
1

1 Study Location

The Refuse Hideaway Landfill is located in Middleton, Wisconsin. The town of Middleton is 

located west of the capital city of Madison. As of the 2000 census, Middleton has a population 

of approximately 16,000 people. It has a humid climate that is characterized by large seasonal 

temperature swings. The winters commonly experience temperatures well below freezing with

moderate to heavy snowfall. The summers are humid and commonly experience temperatures 

between 80o and 90oF. The main utility company is Madison Gas and Electric (MG&E). 

Under the RE-Powering America’s Land Initiative, the Environmental Protection Agency (EPA) 

provided funding to the National Renewable Energy Laboratory (NREL) to support a feasibility 

study of solar renewable energy generation at the Refuse Hideaway Landfill in Middleton, 

Wisconsin. The landfill is 23 acres and sits on a 40-acre parcel of land. The landfill was in 

operation from 1974 through 1988 and is currently closed and capped. Due to the presence of 

contaminants, landfill sites have limited redevelopment potential. Therefore, renewable energy 

generation is a viable reuse. 

One very promising and innovative use of closed landfills is to install solar photovoltaic (PV) 

systems. PV systems can be ground-mounted, and these types of systems work well on landfill 

sites where there are commonly large unshaded areas. In some cases, PV can be used to form the 

cap of the landfill. PV may generate revenue on a landfill site that may otherwise go unused.

The Refuse Hideaway Landfill is owned by the State of Wisconsin, which is interested in 

potential revenue flows from PV systems on landfills. PV systems on landfills may give the state 

a reason to close other state-owned landfills in a timely manner and to maintain the landfill cap 

once it is in place. There is currently a 10 kW ground-mounted crystalline silicon PV system at 

the Refuse Hideaway Landfill, which will be discussed in Section 3.1. 

The focus of this report is on PV systems, but another innovative use of closed landfills is to 

install a landfill gas plant. The landfill gas could be used in a heating application or used to 

operate a generator in order to make electricity. The key points that need to be investigated to 

determine whether landfill gas capture is feasible are the age of the landfill, the size, and the 

types of gases generated by the landfill. For landfill gas capture, it is best to have a newly capped 

landfill because the landfill gas production greatly declines after 20–30 years. It is also 

preferable to have a high organic waste content. The Refuse Hideaway Landfill was closed and 

capped in 1988, and it is therefore not an optimal candidate for a landfill gas plant. The types of 

gases that are generated by the landfill can be determined by doing a sample test. This involves 

drilling a hole into the landfill, putting a vacuum on the landfill, and sampling the rate and types 

of gases being generated. A detailed landfill gas study should be done in order to determine the 

feasibility of landfill gas capture and use at all relatively newly capped larger landfills in the state 

of Wisconsin. 

Like most states, Wisconsin relies heavily on fossil fuels to operate its power plants. About twothirds of Wisconsin’s electricity is generated from coal, and the remaining one-third is generated 
2

from oil, natural gas, or nuclear.

2

• Using fossil fuels to produce power may not be sustainable.

There are many compelling reasons to consider moving toward 

renewable energy sources for power generation instead of fossil fuels, including: 

• Burning fossil fuels can have negative effects on human health and the environment.

• Extracting and transporting fossil fuels can lead to accidental spills, which can be 

devastating to the environment and communities.

• Depending on foreign sources of fossil fuels can be a threat to national security.

• Fluctuating electric costs are associated with fossil-fuel-based power plants. 

• Burning fossil fuels may contribute to climate change. 

• Generating energy without harmful emissions or waste products can be accomplished

through renewable energy sources.

• Abundant renewable resources are available in Wisconsin.

 2 U.S. Energy Information Administration. http://www.eia.doe.gov/state/state_energy_profiles.cfm?sid=WI. 

Accessed November 3, 2010. 
3

2 PV Systems

Solar PV systems are semiconductor devices that convert sunlight directly into electricity. They 

do so without any moving parts and without generating any noise or pollution. They must be 

mounted in an unshaded location; rooftops, carports, and ground-mounted arrays are common 

mounting locations. PV systems work very well in Middleton, Wisconsin, where the average 

global horizontal annual solar resource is 4.6 kWh/m2/day. This number, however, is not the 

amount of energy that can be produced by a PV panel. The amount of energy produced by a

panel depends on several factors. These factors include the type of collector, the tilt and azimuth 

of the collector, the temperature, the level of sunlight, and weather conditions. An inverter is 

required to convert the direct current (DC) to alternating current (AC) of the desired voltage 

compatible with building and utility power systems. The balance of the system consists of 

conductors/conduit, switches, disconnects, and fuses. Grid-connected PV systems feed power 

into the facility’s electrical system and do not include batteries. 

Figure 1 shows the major components of a grid-connected PV system and illustrates how these 

components are interconnected.

Figure 1. Major components of grid-connected PV system

Credit: Jim Leyshon, NREL

PV panels are made up of many individual cells that all produce a small amount of current and 

voltage. These individual cells are connected in series to produce a larger current. PV panels are 

very sensitive to shading. When shade falls on a panel, the shaded portion of the panel cannot 

collect the high-energy beam radiation from the sun. If an individual cell is shaded, it will act as 

a resistance to the whole series circuit, impeding current flow and dissipating power rather than 

producing it. By determining solar access—the unimpeded ability of sunlight to reach a solar 

collector—one can determine whether an area is appropriate for solar panels. 

For this assessment, the NREL team used a solar path calculator to assess shading at particular 

locations by analyzing the sky view where the solar panels will be located. The solar path 

calculator is equipped with a fisheye lens that takes a 360o photo of the sky and plots out the 

shading obstructions throughout the year on a spherical axis, with the months listed 

longitudinally and the hour of day listed latitudinally. Shading analysis is typically done at 
4

locations where shading will most likely be an issue (e.g., close to a group of trees or a hill on 

the perimeter of a landfill). 

If a site is found to have good solar access for a PV system, then the next step is to determine the 

size of that system, which highly depends on the average energy use of the on-site facilities. 

Providing more power than a site would use is dependent on the economics of most net-metering 

agreements. In the case of the Refuse Hideaway site, most of the electricity generated at the site 

would be sold to the serving utility, MG&E, because there is little electrical load except for the 

pumping and fan energy associated with the remediation system. The system size would thus be 

determined by the amount of electricity the electric company would be willing to purchase or by 

how much land area is available. For the purpose of this report, the NREL assessment team 

assumed MG&E would purchase any electricity that the site can generate. The systems will be 

broken down by site so the system size can be adjusted based on what the utility requests.

2.1 Types of PV Systems

2.1.1 Ground-Mounted Systems

A ground-mounted system is required at a landfill because there is little to no roof area. On a 

$/DC-Watt basis, ground-mounted PV systems are usually the lowest cost option to install. 

Several PV panel and mounting options are available, each having different benefits for different 

ground conditions. Table 1 outlines the energy density values that can be expected from each 

type of system. 

Table 1. Energy Density by Panel and System for Ground-Mounted PV

System Type Fixed-Tilt Energy Density

(DC-Watts/ft2

)

Single-Axis Tracking 

Energy Density

(DC-Watts/ft2

)

Crystalline Silicon 4.0 3.3

Thin Film 1.7 1.4

Hybrid HE* 4.8 3.9

* Because hybrid high efficiency (HE) panels do not represent a significant portion of 

the commercial market, they were not included in the analysis. Installing panel types 

that do not hold a significant portion of the commercial market would not be feasible for 

a large-scale solar generation plant.

Installing PV systems on landfills is a unique situation because the landfill cap cannot be 

penetrated. Therefore, a PV system that does not penetrate the landfill cap such as a ballasted 

system is required in landfill applications. With ballasted systems, the PV system is held down 

by weighting the racking system. For the purpose of this analysis, all fixed-tilt systems were 

assumed to be ballasted and mounted at latitude with a tilt of 43.1°. To get the most out of the 

available ground area, considering whether a site layout can be improved to better incorporate a 

solar energy system is important. If unused structures, fences, or electrical poles can be removed, 

the unshaded area can be increased to incorporate more PV panels. When considering a groundmounted system, an electrical tie-in location should be identified to determine how the energy 

would be fed back into the grid. For this report, only fixed-tilt ground-mounted systems and

single-axis tracking systems were considered.
5

Fixed-tilt systems are installed at a specified tilt and are fixed at that tilt for the life of the system. 

Single-axis tracking systems have a fixed tilt on one axis and a variable tilt on the other axis; the 

system is designed to follow the sun in its path through the sky. This allows the solar radiation to 

strike the panel at an optimum angle for a larger part of the day than can be achieved with a 

fixed-tilt system. A single-axis tracking system can collect nearly 30% more electricity per 

capacity than can a fixed-tilt system. The drawbacks include increased operation and 

maintenance (O&M) costs, less capacity per unit area (DC-Watt/ft2), and greater installed costs

($/DC-Watt).

2.1.2 Roof-Mounted Systems

In many cases, a roof is the best location for a PV system. Roof-mounted PV systems are usually 

more expensive than ground-mounted systems, but a roof is a convenient location because it is 

out of the way and usually unshaded. Large areas with minimal rooftop equipment are preferred, 

but equipment can sometimes be worked around if necessary. If a building has a sloped roof, a 

typical flush-mounted crystalline silicon panel can achieve power densities on the order of 

10 DC-Watt/ft2

. For buildings with flat roofs, rack-mounted systems can achieve power densities 

on the order of 8 DC-Watt/ft2 with a crystalline silicon panel. Table 2 lists the energy density by 

panel type for roof-mounted PV. 

Table 2. Energy Density by Panel Type for Roof-Mounted PV

System Type Fixed-Tilt Energy Density

(DC-Watts/ft2

)

Crystalline Silicon 10.0

Thin Film 4.3

Typically, PV systems are installed on roofs that either are less than 5 years old or have over 

30 years left before replacement. There were no roof areas analyzed at the Refuse Hideaway 

Landfill.

2.2 PV System Components

The PV system considered here has these components:

• PV arrays, which convert light energy to DC electricity

• Inverters, which convert DC to AC and provide important safety, monitoring, and 

control functions

• Various wiring, mounting hardware, and combiner boxes

• Monitoring equipment.

2.2.1 PV Array

The primary component of a PV system, the PV array, converts sunlight to electrical energy; all 

other components simply condition or control energy use. Most PV arrays consist of 

interconnected PV modules that range in size from 50 peak DC-Watts to 300 peak DC-Watts. 

Peak watts are the rated output of PV modules at standard operating conditions of 25°C (77°F)

and insolation of 1,000 W/m2. Because these standard operating conditions are nearly ideal, the 
6

actual output will be less under typical environmental conditions. PV modules are the most 

reliable components in any PV system. They have been engineered to withstand extreme 

temperatures, severe winds, and impacts. ASTM E1038-053 subjects modules to impacts from 

one-inch hail balls at terminal velocity (55 mph) at various parts of the module. PV modules 

have a life expectancy of 20–30 years. The array is usually the most expensive component of a 

PV system; it accounts for approximately two-thirds the cost of a grid-connected system. Many

PV manufacturers are available.4

2.2.2 Inverters

PV arrays provide DC power at a voltage that depends on the configuration of the array. This 

power is converted to AC at the required voltage and number of phases by the inverter. Inverters 

enable the operation of commonly used equipment such as appliances, computers, office 

equipment, and motors. Current inverter technology provides true sine wave power at a quality 

often better than that of the serving utility. The locations of both the inverter and the balance-ofsystem equipment are important. Inverters are available that include most or all of the control 

systems required for operation, including some metering and data-logging capability. Inverters 

must provide several operational and safety functions for interconnection with the utility system. 

The Institute of Electrical and Electronic Engineers, Inc. (IEEE) maintains standard “P929 

Recommended Practice for Utility Interface of Photovoltaic (PV) Systems,”5 which allows 

manufacturers to write “Utility-Interactive” on the listing label if an inverter meets the 

requirements of frequency and voltage limits, power quality, and non-islanding inverter testing. 

Underwriters Laboratory maintains “UL Standard 1741, Standard for Static Inverters and 

Charge Controllers for Use in Photovoltaic Power Systems,”6 which incorporates the testing 

required by IEEE 929 and includes design (type) testing and production testing. A large choice 

of inverter manufacturers is available.7

2.3 Operation and Maintenance 

The PV panels come with a 25-year performance warranty. The inverters, which come standard 

with a 5- or 10-year warranty (extended warranties available), would be expected to last 10–15 

years. System performance should be verified on a vendor-provided website. Wire and rack 

connections should be checked. For this economic analysis, an annual O&M cost of 0.17% of 

total installed cost is used based on O&M costs of other fixed-tilt grid-tied PV systems. For the 

case of single-axis tracking, an annual O&M cost of 0.35% of total installed cost is used based 

on O&M costs of existing single-axis tracking systems. 

 3 ASTM Standard E1038. "Standard Test Method for Determining Resistance of Photovoltaic Modules to Hail by 

Impact with Propelled Ice Balls." West Conshohocken, PA: ASTM International, 2005, DOI: 10.1520/E1038-05. 

http://www.astm.org/Standards/E1038.htm. Accessed November 2, 2010. 4 Go Solar California, a joint effort of the California Energy Commission and the California Public Utilities 

Commission, provides consumer information for solar energy systems. See http://www.gosolarcalifornia.org/

equipment/pvmodule.php. Accessed November 2, 2010. 5 “ANSI/IEEE Std 929-1988 IEEE Recommended Practice for Utility Interface of Residential and Intermediate 

Photovoltaic (PV) Systems.” http://standards.ieee.org/reading/ieee/std_public/description/powergen/929-

1988_desc.html. Accessed November 2, 2010. 6 “Inverters, Converters, Controllers and Interconnection System Equipment for Use With Distributed Energy 

Resources: UL 1741.” http://ulstandardsinfonet.ul.com/scopes/1741.html. Accessed November 2, 2010. 7 Go Solar California approves inverters.
7

2.4 PV Size and Performance

PV arrays must be installed in unshaded locations on the ground or on building roofs that have 

an expected life of at least 25 years. The predicted array performance was found using a 

combination of PVWATTS, a performance calculator for grid-connected PV systems created by 

NREL’s Renewable Resource Data Center,

8 and SolOpt, a solar performance tool currently 

being developed at NREL. The performance data was used to calculate the amount of revenue 

that could be expected each year.

 8 NREL. “PVWatts.” http://www.nrel.gov/rredc/pvwatts/. Accessed November 2, 2010.
8

3 PV Site Location

This section summarizes the findings of the NREL solar assessment site visit on April 28, 2010.

3.1 Refuse Hideaway Landfill PV System

The State of Wisconsin is the responsible party at the Refuse Hideaway Landfill because the 

state sent waste there. The site is located to the north of highway 14 and is fairly visible from the 

highway. The Refuse Hideaway Landfill is 23 acres and sits on a 40-acre parcel of land. The 

landfill was in operation from 1974 through 1988 and is currently closed and capped. The 

landfill cap is made up of a minimum of 2 ft of clay, and the landfill is not lined. Some areas of 

the landfill have steep slopes, but there is a relatively large area with moderate to no slope that is 

suitable for a PV system. Figure 2 shows various views of the Refuse Hideaway Landfill. As 

shown, there are large expanses of relatively flat unshaded land, which makes it a suitable

candidate for a PV system.

Figure 2. Views of the feasible area for PV at the Refuse Hideaway Landfill

Credits: Jimmy Salasovich, NREL 

A 10 kW PV system was installed at the Refuse Hideaway Landfill in 2010, and this system 

occupies approximately 1% of the available land that is feasible for a PV system at the site. The 

View to the South

View to the West View to the East

View to the North
9

PV panels used at the site are 224 W crystalline-silicon modules manufactured by Sharp. The 

nameplate of the PV panels is shown in Figure 3. The PV system is a ballasted system so that 

there are no penetrations of the landfill cap. The ballasted system is shown in Figure 4. The area 

that the current 10 kW PV system occupies is approximately 3,400 ft2. The site was relatively 

well kept and mowed at the time of the site visit. Figure 5 shows the 10 kW PV system currently 

in use at the Refuse Hideaway Landfill. 

Figure 3. Sharp PV module nameplate

Credit: Jimmy Salasovich, NREL
10

Figure 4. Ballasted PV system at the Refuse Hideaway Landfill

Credit: Jimmy Salasovich, NREL

Figure 5. View of the 10 kW ballasted PV system currently at the Refuse Hideaway Landfill

Credit: Jimmy Salasovich, NREL
11

The electrical tie-in point and inverter for the PV system at the Refuse Hideaway Landfill is 

located approximately 950 ft to the east of the PV system and is close to the entrance of the 

landfill. A considerable portion of the initial PV system cost was trenching the electrical lines to 

the tie-in point. The electrical tie-in point is shown in Figure 6, and the inverter is shown in 

Figure 7. Expanding the PV system could potentially be started on this site immediately, and the 

costs for trenching the electrical lines to the tie-in point have already been incurred. This site 

would need to have a ballast-mounted system implemented, as ground disturbances are not 

permitted due to the clay cap.

Figure 6. Electrical tie-in point for the PV system at the Refuse Hideaway Landfill

Credit: Jimmy Salasovich, NREL

Figure 7. Inverter used in the PV system at the Refuse Hideaway Landfill

Credit: Jimmy Salasovich, NREL
12

The Refuse Hideaway Landfill has a remediation system that includes fans for methane gas 

extraction and pumps for leachate extraction. There are a total of 13 fans for the methane gas 

extraction and 9 diaphragm pumps for the leachate extraction. The Wisconsin Department of 

Natural Resources (WDNR) has control over the remediation system at the Refuse Hideaway 

Landfill, and it is believed that the remediation system will have to operate indefinitely in order 

to mitigate groundwater contamination. The remediation system consumes approximately 

48,000 kWh/year, which is a relatively significant electrical load at the site. The current 10 kW 

PV system at the site produces approximately 12,310 kWh/year, which is approximately 25% of 

the annual electrical energy required for the remediation system. A 40 kW PV system would 

produce enough electricity to cover the 48,000 kWh annual load at the Refuse Hideaway 

Landfill. 

Figure 8 shows the Refuse Hideaway Landfill taken from Google Earth; the feasible area for PV 

is shaded in orange, the current 10 kW PV system is shaded in green, and the electrical tie-in 

point for the PV system is given. As shown, there is one relatively large area at the Refuse 

Hideaway Landfill that is feasible for PV, which has an area of 378,384 ft2. 

Figure 8. Aerial view of the feasible area (orange) for PV at the Refuse Hideaway Landfill

Credit: Google Earth

Location of current 10 kW PV system

(~3,400 ft2

)

Refuse Hideaway Landfill

PV electrical tie-in point

378,384 ft2
13

Table 3 lists the ground-mounted PV system possibilities at the Refuse Hideaway Landfill. The 

three options outline the types of solar technology that could potentially be used.

Table 3. Refuse Hideaway Landfill PV System Performance and Economics by System Typea

PV System 

Size (kW)

Annual 

Output 

(kWh/year)

Number of 

Houses 

Poweredb

Annual Cost 

Savings 

($/year)

Annual 

O&M 

($/year)

System 

Cost with 

Incentives 

($)

Payback 

Period with 

Incentive 

(years)

Crystalline Silicon (Fixed Tilt 43.1o)

1,350 1,661,850 150 $221,525 $10,328 $4,252,500 20

Crystalline Silicon (Single-Axis Tracking)

1,100 1,549,477 140 $206,545 $23,100 $4,620,000 25

Thin Film (Fixed Tilt 43.1o)

550 677,050 61 $90,251 $3,647 $1,501,500 17 a Data assume a maximum usable area of the Refuse Hideaway Landfill of 378,384ft2

. b Number of average American households that could hypothetically be powered by the PV system 

assuming 11,040 kWh/year/household.9

 9 U.S. Energy Information Administration. http://www.eia.doe.gov/ask/electricity_faqs.asp#electricity_use_home. 

Accessed November 2, 2010.
14

4 Economics and Performance

4.1 Assumptions and Input Data for Analysis

It was assumed that the installed cost of fixed-tilt roof-mounted systems will be $6.00/W and 

fixed-tilt ground-mounted systems will be $4.50/W. These prices include the PV array and the 

balance-of-system components for each system, including the inverter, electrical equipment, and 

installation. The economics of grid-tied PV depend on incentives, the cost of electricity, and the 

solar resource including panel tilt and orientation. For this analysis, it was assumed that the cost 

of electricity was $0.1333/kWh.

A system DC to AC conversion of 77% was assumed. This includes losses in the inverter, wire 

losses, PV module losses, and losses due to temperature effects. PVWATTS was used to 

calculate energy performance.

It was assumed for this analysis that federal and state incentives are received. Identifying and 

leveraging state incentives and grants is an important part of making PV systems cost effective. 

A private, tax-paying entity that owns PV systems can qualify for a 30% federal business energy 

investment tax credit (ITC) and accelerated depreciation on the PV system, which are worth 

about 15%. The total potential tax benefits to the tax-paying entity are about 45% of the system 

cost. Alternatively, the tax-paying entity can opt to receive a cash payment of up to 30% of 

eligible project costs from the U.S. Department of Treasury Section 1603 program10 once the 

eligible system is in service. The American Reinvestment and Recovery Act of 2009 (Recovery 

Act) allows for this cash payment in lieu of the ITC. Because the federal government does not 

pay taxes, private ownership of the PV system is required to capture tax incentives or Section 

1603 grant payments.

11

4.2 Incentives and Financing Opportunities

Municipalities are not tax-paying entities and therefore would have to 

pursue a power purchase agreement (PPA) in order to get the 30% federal tax credit, which is

described in the following section. 

The Database of State Incentives for Renewables and Efficiency (DSIRE) provides a summary 

of net metering, interconnection rules, and other incentives available to Middleton, Wisconsin,

utility customers. 

Renewable energy systems, including commercial solar PV, are subject to interconnection rules 

promulgated at the state level. Interconnection rules for Wisconsin were found on the DSIRE 

website. The Wisconsin Public Service Commission developed interconnection standards in 

2004 that set an interconnection system capacity limit at 15 MW. This requires all interconnected 

systems to comply with the safety and performance requirements put forth in the IEEE Standard 

1547 as well as local construction and safety standards. 

Wisconsin has a net-metering policy for residential, commercial, and industrial systems up to 

20 kW in capacity. This is a very low capacity for net metering and is an issue for the Refuse 

Hideaway Landfill because not all of the electricity generated by a PV system will be used, so 

 10 This program was codified in Section 1603 of the American Recovery and Reinvestment Act of 2009. 11 DSIRE. “Wisconsin.” http://www.dsireusa.org/incentives/index.cfm?re=1&ee=1&spv=0&st=0&srp=1&state=WI.

 Accessed November 2, 2010.
15

the remaining will have to be sent back to the electric utility grid. Discussions with MG&E 

should commence to determine if the net-metering capacity limit can be significantly raised if a 

PV system were to be installed at the Refuse Hideaway Landfill. Net excess generation will be 

carried over to a customer-generator's next bill. 

State incentives are currently not offered for solar power systems in Wisconsin. The 30% tax 

credit federal incentive can be captured if the system is owned by a tax-paying entity.

The system facilitator could potentially pursue an agreement with MG&E that would negotiate 

both a higher price for the electricity produced by the PV system and the potential to sell 

renewable energy certificates (RECs). Any power that is produced by a solar PV system will 

help the state reach its renewable portfolio standard (RPS) and would be a major opportunity for 

MG&E to accelerate the diversification of their energy mix with clean energy. It has been 

demonstrated across the country that people are willing to pay a premium for certified clean 

energy,12 and MG&E could start a voluntary green power purchase pilot program with energy 

from the Refuse Hideaway Landfill.

13

Technical assistance to support project development is available through the U.S. Department of 

Energy (DOE) and the Office of Energy Efficiency and Renewable Energy (EERE). The 

program provides technical assistance to commercial power developers, technology projects 

involving liquid fuels developed from biomass, and information to the public on renewable 

energy applications. The DOE Office of EERE can assist commercial wind and solar developers 

by providing detailed renewable resource maps, interfacing with Wisconsin utilities, and 

contacting local economic developers.

There are several options for financing a solar PV system. However, obtaining investment from 

landowners with little on-site presence—such as is the case with the Refuse Hideaway 

Landfill—can be difficult. A potential alternative financing option is the third-party ownership 

PPA. The agreement works by having a solar contractor install, finance, and operate the system 

while the utility company purchases the electricity generated by the system. The system is 

financed by the solar contractor, and the payments are paid by the electricity and RECs that are 

sold to the utility. In this configuration, the land that the solar system is on would need to be 

leased to the owner of the system for the duration of the contract.

Another gap financing tool that may be available is tax increment financing (TIF). Connecticut, 

Iowa, Michigan, and Wisconsin have been leaders in structuring state-facilitated TIF financing as 

an effective and efficient means to enhance site reuse and redevelopment programs and to obtain 

successful cleanup and redevelopment results. A full list of incentives can be found in 

Appendix B. 

 12 Transmission & Distribution World. “NREL Highlights Utility Green Power Leaders.”

http://tdworld.com/customer_service/doe-nrel-utility-green-power-0409/. Accessed November 2, 2010. 13 An example of such a program is Xcel Energy’s Windsource program. For more information, see http://www

.xcelenergy.com/Colorado/Company/Environment/Renewable%20Energy/Pages/Wind_Power.aspx. Accessed 

November 2, 2010. For detailed information about federal, state, and local incentives in Wisconsin, see 

http://www.dsireusa.org/incentives/index.cfm?re=1&ee=1&spv=0&st=0&srp=1&state=WI. Accessed November 2, 

2010.
16

4.3 Job Creation

The implementation of this project would represent a large amount of money entering the clean 

energy industry of Wisconsin. The Council of Economic Advisors (CEA) calculated the number 

of jobs (direct, indirect, and induced) created due to federal spending using economic models 

developed with real world data. CEA found that $92,000 in federal spending is equivalent to one 

job-year. This means that for every $92,000 of federal money that is spent, there is a job created 

that can be sustained for 1 year. See Table 4 for an estimate of job creation by system type if all 

the feasible area at the Refuse Hideaway Landfill were used for solar PV. This project represents 

a large amount of money that would create a significant number of jobs. A portion of these jobs, 

including the installation and system maintenance jobs, will be created within the community. 

The jobs created column refers to the number of job-years that would be created as a result of the 

one-time project capital investment. This means that the jobs will be created and sustained for 

one year. The jobs sustained column refers to the number of jobs that would be sustained as a 

result of the O&M of the system. These jobs will be sustained for the life of the system, due to 

the annual cost to keep the system operating. 

Table 4. Estimated Job Creation by PV System Type

System Type Jobs Createda

(job-years)

Jobs Sustainedb

(number of jobs)

Crystalline Silicon (Fixed Tilt) 66 0.11

Crystalline Silicon (Single-Axis Tracking) 72 0.25

Thin Film (Fixed Tilt) 23 0.04 a Job-years created as a result of project capital investment including direct, indirect, and induced jobs. b Jobs (direct, indirect, and induced) sustained as a result of O&M of the system.
17

5 Potential Rate Increases 

The economics of a potential PV system on the Refuse Hideaway Landfill depend greatly on the 

cost of electricity. Currently, MG&E has an average electric rate of $0.1333/kWh. Based on past 

electric rate increases in Wisconsin, this rate could hypothetically increase to $0.15/kWh or 

higher in a relatively short amount of time. A rate increase of this magnitude would further 

improve the economics of a solar PV generation plant. See Table 5 for a summary of the system 

economics assuming a hypothetical rate increase to $0.15/kWh.

Table 5. PV System Performance and Economics with a Hypothetical Rate Increase to $0.15/kWha

PV System 

Size (kW)

Annual 

Output 

(kWh/year)

Number of 

Houses 

Poweredb

Annual Cost 

Savings 

($/year)

Annual 

O&M 

($/year)

System 

Cost with 

Incentives 

($)

Payback 

Period with 

Incentive 

(years)

Crystalline Silicon (Fixed Tilt 43.1o)

1,350 1,661,850 150 $249,278 $10,328 $4,252,500 18

Crystalline Silicon (Single-Axis Tracking)

1,100 1,549,477 140 $232,422 $23,100 $4,620,000 22

Thin Film (Fixed Tilt 43.1o)

550 677,050 61 $101,558 $3,647 $1,501,500 15 a Data assume a maximum usable area of the Refuse Hideaway Landfill of 378,384ft2

. b Number of average American households that could hypothetically be powered by the PV system 

assuming 11,040 kWh/year/household.14

 14 U.S. Energy Information Administration. http://www.eia.doe.gov/ask/electricity_faqs.asp#electricity_use_home. 

Accessed November 2, 2010.
18

6 Conclusions and Recommendations 

The Refuse Hideaway Landfill considered in this report is a feasible location to implement solar 

PV systems. Using obtainable and accessible land that is unavailable for other purposes allows 

for reuse of land that would not otherwise contribute to productivity for Middleton, Wisconsin. 

Installing a solar generation plant and the associated facilities on landfills relieves “greenfields” 

of land use impacts. The results from the Refuse Hideaway Landfill can be extrapolated to cover 

other landfills throughout Wisconsin. Developing solar facilities on landfills can provide an 

economically viable reuse option for landfills in Wisconsin. It is beneficial for the landfills to

have existing transmission capacity, roads, industrial zoning, and all other critical infrastructure 

in place for PV systems. One obstacle to PV on landfills is that landfills require little to no 

electricity once they are capped and closed. Therefore, finding a use for the electricity generated 

by the PV system is a key element. 

It is recommended that the party ultimately responsible for facilitating the implementation of the 

PV system contact MG&E and attempt to set up an agreement in which MG&E would purchase 

the electricity generated at the Refuse Hideaway Landfill. According to the site production 

calculations, the most cost-effective system in terms of return on investment is the thin-film 

fixed-tilt technology. The lower cost of the system combined with the ample land available 

makes a thin-film system a good fit for the Refuse Hideaway Landfill. Thin-film technology is a 

proven technology that can be successfully implemented with a ballasted-style mounting system. 

Crystalline silicon system styles—both fixed tilt and single-axis tracking systems—could also be 

implemented, but the increased cost of the crystalline silicon panels may extend the payback 

period.

For this feasibility study, system calculations and sizes were based on site area; however, actual 

system installation should be based on the availability of funds or on the amount of power that 

can be sold. There is currently a 10 kW PV system at the Refuse Hideaway Landfill, so adding 

capacity as funding becomes available might make sense. When the system goes out to bid, a 

design-build contract should be issued that requests the best performance (kWh/year) at the best 

price and that allows vendors to optimize system configuration, including slope. A third-party 

ownership PPA provides the most feasible way for a system to be financed on these sites. All 

payback calculations assumed that the 30% federal tax credit would be captured for the systems. 

In the coming years, increasing electrical rates and increased necessity for clean power will 

continue to improve the feasibility of implementing solar PV systems at landfill sites in 

Wisconsin. 
19

Appendix A. Assumptions for Calculations15

Table A-1. Calculation Assumptions for Ground-Mounted PV Systems at the Refuse Hideaway Landfill Using Current Electric Rate of $0.1333/kWh

Location

Array Tilt 

(Deg)

Max Usable 

Area (ft2)

Rounded PV System 

Size (kW)

Annual Output 

(kWh/year)

Annual Cost Savings 

($/year)

Annual O&M 

($/year)

System Cost with 

Incentives ($)

Payback Period 

(years)

Crystalline Silicon (Fixed Tilt)

Refuse Hideaway 43.1 378,384 1,350 1,661,850 $221,525 $10,328 $4,252,500 20

Crystalline Silicon (Single-Axis Tracking)

Refuse Hideaway 0 378,384 1,100 1,549,477 $206,545 $23,100 $4,620,000 25

Thin Film ( Fixed Tilt)

Refuse Hideaway 43.1 378,384 550 677,050 $90,251 $3,647 $1,501,500 17

Table A-2. Calculation Assumptions for Ground-Mounted PV Systems at the Refuse Hideaway Landfill Using Hypothetical Electric Rate of $0.15/kWh

Location

Array Tilt 

(Deg)

Max Usable 

Area (ft2)

Rounded PV System 

Size (kW)

Annual Output 

(kWh/year)

Annual Cost Savings 

($/year)

Annual O&M 

($/year)

System Cost with 

Incentives ($)

Payback Period 

(years)

Crystalline Silicon (Fixed Tilt)

Refuse Hideaway 43.1 378,384 1,350 1,661,850 $249,278 $10,328 $4,252,500 18

Crystalline Silicon (Single-Axis Tracking)

Refuse Hideaway 0 378,384 1,100 1,549,477 $232,422 $23,100 $4,620,000 22

Thin Film (Fixed Tilt)

Refuse Hideaway 43.1 378,384 550 677,050 $101,558 $3,647 $1,501,500 15

 15 The calculations in Appendix A assume that the 30% federal tax credit is secured.
20

Table A-3. Other Assumptions, Including Assumptions for Costs and System Types

Cost Assumptions

Variable Quantity of Variable Unit of Variable

Cost of Site Electricity $0.1333 $/kWh

Annual O&M (Fixed) 0.17% % of installed cost

Annual O&M (Tracking) 0.35% % of installed cost

System Assumptions

System Type

Annual energy

(kWh/kW)

Installed Cost

($/W)

Energy Density

(W/ft2

)

Ground Crystalline Fixed 1,231 $4.50 4.0

Ground Single-Axis Tracking 1,409 $6.00 3.3

Ground Thin-Film Fixed

Roof Crystalline Fixed

Roof Thin-Film Fixed

1,231

1,231

1,231

$3.90

$6.00

$5.40

1.7

10.0

4.3

Other Assumptions Ground utilization 90% of available area

Incentives Federal tax credit
21

Appendix B. Renewable Energy Incentives16

Table B-1. Redevelopment and Renewable Energy Incentives and Financing Tools

Agency Incentive Name

Incentive (I), 

Finance Tool 

(FT) Public Private Funding Range

HUD Brownfield Economic Development Initiative 

(BEDI) Competitive Grant Program

I X Xa $17.5 million appropriated in FY 2010. 

Award cap TBD as of 2/27/10.

HUD Section 108 Loan Guarantee Program FT X Xb Up to five times public entity’s latest 

approved Community Development 

Block Grant (CDBG) amount. a Must be used in conjunction with Section 108 loan guarantee commitment.

b Through re-loan from public entity.

 16 The calculations in Appendix B assume that the 30% federal tax credit is secured.
22

Table B-2. Renewable Energy Development Incentives and Financing Tools Applicable to PV17,18

Agency Incentive Name

Incentive (I), 

Finance Tool 

(FT) Public Private Funding Range

DOE Loan Guarantee Program FT X X Not specified

DOE Renewable Energy Production Incentive 

(REPI) I X $0.021/kW

HUD Community Development Block Grants 

(CDBG) I X Based on community needs formula

Treasury 1603 Renewable Energy Grant Program

*option to ITC I X 30% of the cost basis of the 

renewable energy project

Treasury Business Energy ITC *option to 1603 I X 30% of project expenditures

Treasury Clean Renewable Energy Bonds (CREB) FT X Varies

Treasury Modified Accelerated Cost-Recovery 

System (MACRS) FT X Various depreciation deductions

Treasury Qualified Energy Conservation Bonds 

(QECB) FT X Varies

USDA Rural Energy for America Program (REAP) 

Grants I X X 25% of project cost. Payment range $2.5K–$500K

USDA REAP Loan Guarantees FT X X Up to 75% of project costs. Max. $25 

million/Min. $5,000

 17 DSIRE. http://www.dsireusa.org/. Accessed September 2010. 18 U.S. Department of Housing and Urban Development 2009. http://www.hud.gov/. Accessed September 2010.
23

Table B-3. State Rebates for Commercial-Sector PV Projects19

The programs included here are ongoing rebate and grant programs administered by state agencies or by third-party organizations on 

behalf of state governments. In addition to the programs highlighted, about 75 utilities in the United States offer PV rebates. In some 

states, such as Colorado and Arizona, solar rebates from utilities are available nearly statewide that must comply with state RPSs, but 

these are not shown in the table. Finally, programs that are purely performance-based, such as Washington's production incentive and 

California's feed-in tariff, are not included in this table.

State Program Name Incentive Amount REC Ownership Funding Source

California California Solar Initiative Varies by sector and system size. Remains with project 

owner

Rate-payer funded

California CEC - New Solar Homes 

Partnership

Varies. Incentives are adjusted 

based on expected performance and 

will decline over time based on the 

total installed capacity.

Remains with system 

owner

Rate-payer funded

Connecticut Connecticut Clean 

Energy Fund (CCEF) -

On-Site Renewable DG 

Program

For-profit owners: $3.00/W for first 

100 kW, $2.00/W for next 100 kW. 

Not-for-profit owners: $4.50/W for 

first 100 kW, $4.00/W for next 100 

kW. Additional $0.10/W premium for 

buildings that meet LEED Silver 

certification. CCEF also 

compensates system owners based 

on the estimated present value of the 

system's RECs.

RECs transfer to CCEF 

for systems 50 kW-PTC 

and larger. CCEF 

compensates system 

owners based on 

estimated present value 

of the system's RECs 

over 15 years.

CCEF (public benefits fund)

Delaware Green Energy Program 

Incentives

Delmarva: 25% of installed cost 

(35% for non-profits and 

government); DEC: 33.3% of 

installed cost; Minis: 33.3% of 

installed cost, except 25% for Dover 

and Seaford; PV system cost may 

not exceed $12/W.

Remains with project 

owner

Green Energy Fund (Delmarva), 

DEC Renewable Resources 

Fund, Municipal Utility Green 

Energy Fund (public benefits 

fund)

District of 

Columbia

Renewable Energy 

Incentive Program

$3/DC-Watt for first 3 kW; $2/DCWatt for next 7 kW; $1/DC-Watt for 

next 10 kW

Remains with system 

owner

Sustainable Energy Trust Fund 

(public benefits fund)

 19 DSIRE. http://www.dsireusa.org/. Accessed September 2010.
24

State Program Name Incentive Amount REC Ownership Funding Source

Florida Solar Energy System 

Incentives Program

$4/DC-Watt Remains with system 

owner

General Revenue Funds 

(appropriated annually)

Illinois DCEO - Solar and Wind 

Energy Rebate Program

Residential and commercial: 30%; 

non-profit and public: 50%. Note 

(02/2010): Funding for FY 2010 has 

been fully allocated; no additional 

rebates are available.

Remains with 

customer/producer

Illinois Renewable Energy 

Resources Trust Fund (public 

benefits fund)

Maine Solar and Wind Energy 

Rebate Program

$2/AC-Watt Remains with 

customer/producer

Funded by assessment of up to 

0.005 cents/kWh on transmission 

and distribution utilities plus 

$500,000 per fiscal year (FY

2009–2010 and FY 2010–2011)

for 2 years using Recovery Act 

funding

Maryland Mid-Size Solar Energy 

Grant Program

$500/kW for first 20 kW; $250/kW for 

next 30 kW; $150/kW for next 50 kW

Remains with project 

owner

Recovery Act

Maryland Solar Energy Grant 

Program

$1.25/DC-Watt for first 2 kW; 

$0.75/W for next 6 kW; $0.25/W for 

next 12 kW

Remains with project 

owner

General Revenue Funds 

(appropriated annually); FY 2009 

funds supplemented with RGGI 

proceeds

Massachusetts CEC - Commonwealth 

Solar II Rebates

$1.00/DC-Watt base; $0.10/DC-Watt 

adder for MA components; 

$1.00/DC-Watt adder for moderate 

home value or for moderate income

Remains with project 

owner

Massachusetts Renewable 

Energy Trust

Massachusetts CEC - Commonwealth 

Solar Stimulus

$1.50/DC-Watt for first 25 kW; 

$1.00/DC-Watt for 25–100 kW; 

$0.50/DC-Watt for 100–200 kW

Remains with project 

owner

Recovery Act

Nevada NV Energy – Renewable 

Generations Rebate 

Program

(2010–2011 program year) 

Residential and small business: 

$2.30/AC-Watt; public 

facilities/schools: $5.00/AC-Watt

NV Energy Rate-payer funded

New Jersey New Jersey CustomerSited Renewable Energy 

Rebates

Standard residential: $1.55/DC-Watt; 

residential with energy efficiency: 

$1.75/DC-Watt; residential new 

construction: varies by efficiency, 

$1.00–$1.75/DC-Watt; standard nonRemains with project 

owner

New Jersey Societal Benefits 

Charge (public benefits fund)
25

State Program Name Incentive Amount REC Ownership Funding Source

residential: $0.90/DC-Watt; nonresidential with efficiency: $1.00/DCWatt

New Jersey Renewable Energy 

Manufacturing Incentives 

(for end-use PV 

installations)

Varies by equipment type, sector, 

and system size; ranges from $0.05–

$0.55/DC-Watt.

Not applicable New Jersey Societal Benefits 

Charge (public benefits fund)

New York NYSERDA - PV Incentive 

Program

Residential (first 5 kW): $1.75/DCWatt; non-residential (first 50 kW): 

$1.75/DC-Watt; non-profit, 

government, schools (first 25 kW): 

$1.75/DC-Watt; bonus incentive: 

$0.50/W for Energy Star homes and 

BIPV systems

First 3 years: 

NYSERDA, thereafter 

customer/generator

RPS surcharge

Ohio ODOD - Advanced 

Energy Program Grants -

Non-Residential 

Renewable Energy 

Incentive

$3.50/DC-Watt, may be reduced by 

shading

Not specified Ohio Advanced Energy Fund

Oregon Energy Trust - Solar 

Electric Buy-Down 

Program

Residential: $1.50/DC-Watt for 

Pacific Power; $1.75/DC-Watt for 

PGE; residential, third-party: $1/DCWatt for Pacific Power; $1.25/DCWatt for PGE; commercial: $0.50–

$1.00/W for Pacific Power; $0.75–

$1.25/W for PGE; nonprofit/government: $0.75–$1.25/W 

for Pacific Power; $1.00–$1.50/W for 

PGE

Residential: RECs for 

first 5 years owned by 

customer/producer; 

non-residential: RECs 

for first 5 years owned 

by consumer/producer, 

then Energy Trust owns 

RECs for years 6–20

Energy Trust of Oregon (public 

benefits fund)

Pennsylvania Pennsylvania Sunshine 

Solar Rebate Program

Residential: $2.25/DC-Watt; 

commercial: $1.25/DC-Watt for first 

10 kW, $1.00/DC-Watt for next 90 

kW, $0.75/DC-Watt for next 100 kW; 

low-income: 35% of installed costs

Not specified; netmetering customers 

generally retain title to 

RECs

Pennsylvania Energy 

Independence Fund (state bonds)

Puerto Rico Puerto Rico - State 

Energy Program - Sun 

Energy Rebate Program

Solar PV: residential and commercial 

$4/DC-Watt; governmental $8/DCWatt 

Not addressed Recovery Act State Energy 

Program funds
26

State Program Name Incentive Amount REC Ownership Funding Source

Tennessee Tennessee Clean Energy 

Technology Grant

40% of installed cost Not specified State of Tennessee Economic 

and Community Development 

Energy Division

Vermont Vermont Small-Scale 

Renewable Energy 

Incentive Program

Individuals/businesses: $1.75/DCWatt; multi-family, low-income: 

$3.50/DC-Watt

Not addressed Utility settlement funds and the 

Vermont Clean Energy 

Development Fund

Wisconsin Focus on Energy -

Renewable Energy CashBack Rewards

Residential/businesses: $1.00/kWh 

for one year; non-profit/government: 

$1.50/kWh for one year (estimated 

one year production using 

PVWATTS). Efficiency First 

participants: add $0.25/kWh for one 

year.

Not addressed Focus on Energy Program

Note: The information provided in this table presents an overview of state incentives, but it should not be used as the only source of information 

when making purchasing decisions, investment decisions, tax decisions, or other binding agreements. For more information about individual 

programs listed above, visit the DSIRE website at http://dsireusa.org/solar/comparisontables/.
27

Table B-4. State Tax Credits for Commercial-Sector PV Projects20

State Program Name Eligible Recipients

Incentive 

Amount

Third-Party Owner 

Eligible

Non-Profit/Government 

Eligible

Arizona Non-Residential 

Solar & Wind 

Tax Credit 

(Corporate)

Any non-residential installation is 

eligible, including those for nonprofits and governments. 

Individuals, corporations and S 

corporations, and partnerships may 

claim the credit. Third-party 

financiers/installers/mfrs. of eligible 

system may claim the credit.

10% Yes Yes

Florida Renewable 

Energy 

Production Tax 

Credit

A non-residential taxpayer with 

facility placed in service or 

expanded after May 1, 2006. The 

credit is for electricity produced and 

sold by the taxpayer to an unrelated 

party during a given tax year. 

Florida corporate income taxpayers 

who own an interest in a general 

partnership, limited partnership, 

limited liability company, trust, or 

other artificial entity that owns a 

Florida renewable energy facility 

can apply for this credit.

$0.01/kWh Not specified Not specified

Georgia Clean Energy 

Tax Credit 

(Corporate)

Taxpayer who has constructed, 

purchased, or leased renewable 

energy property and placed it in 

service.

35% Yes Not specified

Hawaii Solar and Wind 

Energy Credit 

(Corporate)

Taxpayer that files a corporate net 

income tax return or franchise tax 

return; credit may be claimed for 

every eligible renewable energy 

technology system that is installed 

and placed in service. Third-party 

taxpaying entities may claim the 

credit if they install and own a 

35% Yes Yes

 20 DSIRE. http://www.dsireusa.org/. Accessed September 2010.
28

State Program Name Eligible Recipients

Incentive 

Amount

Third-Party Owner 

Eligible

Non-Profit/Government 

Eligible

system on a commercial taxpayer’s 

building or on a non-profit or 

government building. Multiple 

owners of a single system may take 

a single tax credit. The credit is 

apportioned between the owners in 

proportion to their contribution to the 

system's cost.

Iowa Renewable 

Energy 

Production Tax 

Credits 

(Corporate)

Producers or purchasers of 

renewable energy from qualified 

facilities; installations must be at 

least 51% owned by a state resident 

or other qualifying owner and placed 

in service on or after July 1, 2005, 

and before January 1, 2012. 

Electricity must be sold to an 

unrelated person to qualify for the 

tax credit.

$0.015/kWh for 

10 years after 

energy 

production 

begins

Yes, credits may be 

claimed by system owner 

or by electricity purchaser. 

System owners must meet 

certain eligibility criteria.

Schools and cooperative 

associations are eligible 

owners. Credits may be 

transferred or sold one 

time.

Kentucky Renewable 

Energy Tax 

Credit 

(Corporate)

Any installation on a dwelling unit or 

on property that is owned and used 

by the taxpayer as commercial 

property.

$3/DC-Watt Not specified Not specified

Kentucky Tax Credit for 

Renewable 

Energy 

Facilities

Companies that build or renovate 

facilities that utilize renewable 

energy.

100% Kentucky 

income tax or 

limited liability 

entity tax

Not specified Not specified

Louisiana Tax Credit for 

Solar and Wind 

Energy 

Systems on 

Residential 

Property 

(Corporate)

Taxpayer who purchases and 

installs an eligible system or who 

purchases a new home with such a 

system already in place.

50% No No
29

State Program Name Eligible Recipients

Incentive 

Amount

Third-Party Owner 

Eligible

Non-Profit/Government 

Eligible

Maryland Clean Energy 

Production Tax 

Credit 

(Corporate)

All individuals and corporations that 

sell electricity produced by a 

qualified facility to an unrelated 

person; net-metering arrangements 

qualify.

$0.0085/kWh 

for 5 years after 

facility is placed 

in service

Not specified No

Montana Alternative 

Energy 

Investment Tax 

Credit 

(Corporate)

Corporation, partnership, or small 

business corporation that makes a 

minimum investment of $5,000.

35% No No

New 

Mexico

Advanced 

Energy Tax 

Credit 

(Corporate)

Any taxpayer. 6% No No

New 

Mexico

Renewable 

Energy 

Production Tax 

Credit 

(Corporate)

Taxpayer who holds title to a 

qualified energy generator that first 

produced electricity on or before 

January 1, 2018, or a taxpayer who 

leases property upon which a 

qualified energy generator operates 

from a county or municipality under 

authority of an industrial revenue 

bond and if the qualified energy 

generator first produced electricity 

on or before January 1, 2018.

Varies annually 

over 10 years; 

$0.027/kWh 

average

Not specified Not specified

New 

Mexico

Solar Market 

Development 

Tax Credit

Residents and non-corporate 

businesses, including agricultural 

enterprises.

10% of 

purchase and 

installation 

costs

No No
30

State Program Name Eligible Recipients

Incentive 

Amount

Third-Party Owner 

Eligible

Non-Profit/Government 

Eligible

North 

Carolina

Renewable 

Energy Tax 

Credit 

(Corporate)

Taxpayer who has constructed, 

purchased, or leased renewable 

energy property and placed it in

service.

35% 

(distributed 7% 

per year for 5 

years for nonresidential 

installations)

Yes. For leasing, a 

taxpayer may take credit 

for property that the 

taxpayer leases if written 

verification is received 

from the owner that states 

that the owner will not take 

credit for renewable 

energy installation.

No

North 

Dakota

Renewable 

Energy Tax 

Credit

Corporate taxpayers filing a North 

Dakota income tax return. System 

must be installed on a building or on 

property owned or leased by the 

taxpayer in North Dakota.

15% 

(distributed 3% 

per year for 5 

years)

A pass-through entity that 

installs the system at a 

property it owns or leases 

is considered the taxpayer. 

The credit amount allowed 

is determined at the passthrough entity level and 

must be passed through 

proportionally to corporate 

partners, shareholders, or 

members.

No

Oklahoma Zero-Emission 

Facilities 

Production Tax 

Credit

Non-residential taxpayer who sells 

electricity to an unrelated person; 

non-taxable entities, including 

agencies of the State of Oklahoma, 

may transfer their credit to a 

taxpayer.

$0.005/kWh for 

first 10 years of 

operation

Yes Yes, nontaxable entities, 

including agencies of the 

State of Oklahoma, or 

political subdivisions 

thereof, can take 

advantage of the tax credit 

by transferring it to a 

taxable entity.

Oregon Business 

Energy Tax 

Credit

Trade, business, or rental property 

owners who pay taxes for a 

business site in Oregon are eligible 

for the tax credit. The business, its 

partners, or its shareholders may 

use the credit. A project owner also 

can be an Oregon non-profit 

organization, tribe, or public entity 

that partners with an Oregon 

50% 

(distributed 

10% per year 

for 5 years)

Yes A project owner can be a 

non-profit, tribe, or public 

entity that partners with a 

business or resident to 

take advantage of the 

pass-through option. The 

pass-through option allows 

a project owner to transfer 

the 35% Business Energy 
31

State Program Name Eligible Recipients

Incentive 

Amount

Third-Party Owner 

Eligible

Non-Profit/Government 

Eligible

business or resident who has an 

Oregon tax liability. This can be 

done using the pass-through option.

Tax Credit project eligibility 

to a pass-through partner 

for a lump-sum cash 

payment. The passthrough option rate for 5-

year Business Energy Tax 

Credits effective October 

1, 2003, is 25.5%. The 

pass-through option rate 

for 1-year Business Energy 

Tax Credits (those with 

eligible costs of $20,000 or 

less) effective October 1, 

2003, is 30.5%.

Puerto 

Rico

Puerto Rico -

Solar Tax 

Credit 

(Corporate)

Any Puerto Rican taxpayer who has 

acquired, assembled, and installed 

eligible solar electric equipment.

75% during FY 

2007–2008 and 

FY 2008–2009; 

50% during FY 

2009–2010 and 

FY 2010–2011; 

25% starting FY 

2011–2012

Not specified Potentially; the tax credit 

may be transferred, sold, 

or otherwise given to "any 

other person."

Rhode 

Island

Residential 

Renewable 

Energy Tax 

Credit 

(Corporate)

Taxpayer who (1) owns, rents, or is 

the contract buyer of the dwelling(s) 

served by the system; the dwelling 

or dwellings must be in the main or 

secondary residence of the person 

who applies for the tax credit or of a 

tenant; (2) owns or is the contract 

buyer of the system and pays all or 

part of the cost of the system; or (3) 

is the contractor that owns the 

dwelling for speculative sale in 

which the system is installed.

25% Yes. Credit is available to 

taxpayers who are the 

contract buyers of eligible 

systems and pay all or part 

of the cost of the system.

No
32

State Program Name Eligible Recipients

Incentive 

Amount

Third-Party Owner 

Eligible

Non-Profit/Government 

Eligible

South 

Carolina

Solar Energy 

and Small 

Hydropower 

Tax Credit 

(Corporate)

Taxpayers who purchase and install 

an eligible system in or on a facility 

owned by the taxpayer.

25% for 2010; 

was 30% in 

2009

No No

Utah Renewable 

Energy 

Systems Tax 

Credit 

(Corporate)

Any company that owns a qualified 

system.

Residential: 

25%; 

Commercial: 

10%

No No

Vermont Business Tax 

Credit for Solar 

(Corporate)

Corporations that pay corporate 

income tax in Vermont that do not 

receive grants/funding from CEDF.

30% of 

expenditures for 

systems placed 

into service on 

or before 

December 31, 

2010

Not specified No

West 

Virginia

Residential 

Solar Energy 

Tax Credit

Any taxpayer who installs (or 

contracts for the installation of) an 

eligible solar system on residential 

property that he/she owns and uses 

as a residence in the state.

30% Not specified No

Note: The information provided in this table presents an overview of state incentives, but it should not be used as the only source of information 

when making purchasing decisions, investment decisions, tax decisions, or other binding agreements. For more information about individual 

programs listed above, visit the DSIRE website at http://dsireusa.org/solar/comparisontables/.
33

Table B-5. U.S. Department of Energy Brightfields Program Grants21

Award 

Year

Award 

Amount

Project Project Description Project Status

2000 $30,000 Brockton, MA: 

Brownfields to 

Brightfields Project

“This project involved attracting a PV system manufacturer to a Brockton 

Brownfield and building a solar array on a second site. Anticipation: This 

array will bring into productive use up to 27 acres of idle property and 

the array could also generate up to 6 MW of electricity. To create 

sufficient local demand to attract the manufacturer, other potential sites 

for photovoltaic applications will be surveyed.”

425 kW facility 

commercially operational 

since September 27, 

2006. Expanded by 35 

kW to 460 kW in July 

2007; grid-connected 

and selling 100% of 

output into New England 

Power Pool

$50,000 Atlantic City, NJ: 

Cityscape SolarPowered Bed and 

Breakfast on an 

Urban Brownfield.

“Involves the construction of a solar-powered bed and breakfast on an 

urban brownfield site in Atlantic City, New Jersey, as part of an overall 

neighborhood redevelopment plan with a sustainability theme. The 

project will showcase the use of PV in supplying renewable energy and 

also contain sustainable features such as recycled building materials 

and Energy Star appliances and will be located in the ‘Cityscape 

Neighborhood,’ an area designed to promote renewable energy, 

sustainable building materials, and concepts of New Urbanism.”

Project canceled

$50,000 Hanford, WA: 

Brightfield Project

“This project will ultimately be the largest PV installation of its kind and 

will bring the Brightfield concept to one of the worst Super Fund sites in 

the nation. The funding provided will cover a portion of the pilot phase of 

the project, involving 40 kW. Later phases will use a wind/solar green 

energy blending strategy to finance development up to 1 MW or larger. 

This solar array will act as a nucleation site around which Energy 

Northwest intends to grow a renewable energy industrial park.”

38.7 kW system installed 

in May 2002

 21 U.S. DOE State Energy Program 2006. http://www.energy.gov/. Accessed September 2010.
34

2004 $65,400 Cedar Rapids, IA: 

Bohemian 

Commercial Historic 

District Solar 

Development 

Program

“The Iowa Department of Natural Resources (IDNR) will partner with the 

City of Cedar Rapids, the Iowa Renewable Energy Association, Alliant 

Energy, and Thorland Company to install a 7,200-watt solar array in 

Cedar Rapids on a multiuse converted former warehouse building in a 

designated brownfields redevelopment area. The IDNR has established 

partnerships with the City of Cedar Rapids, Alliant Energy, the Iowa 

Renewable Energy Association, and the building owner to increase the 

economic and environmental viability of a redeveloped brownfield area 

and expand the value and viability of solar projects.”

7.2 kW installed

$59,400 Brockton, MA: Solar 

Energy Park: 

Deploying a Solar 

Array on a Brownfield

“The City of Brockton will build New England's largest solar array at a 

remediated 27-acre brownfield site in fall 2004. The 500-kW solar PV 

array—or ‘Brightfield’—will be installed in an urban park setting with 

interpretive displays. The Brightfield could include as many as 6,720 

solar panels connected in strings that span the site. The Brightfield will 

grow incrementally to 1 MW with expansions financed through positive 

annual cash flow generated by the sale of RECs and electricity.”

425 kW facility 

commercially operational 

since September 27, 

2006. Expanded by 35 

kW to 460 kW in July 

2007; grid-connected 

and selling 100% of 

output into New England 

Power Pool

$125,000 Raleigh, NC: 

Brightfield Technology 

Demonstration at 

NCSU

“Carolina Green Energy, LLC proposes to partner with the North 

Carolina Solar Center to design and install a 30-kW grid-tied PV system. 

As part of its continued efforts to bolster support for renewable energy, 

the Solar Center will incorporate the ‘Brownfield to Brightfield’ project at 

Lot 86 into its ongoing education and outreach programs.”

75.6 kW PV generation 

project operational since 

October 2007

According to EPA, the term brightfields refers to “the conversion of contaminated sites into usable land by bringing pollution-free solar energy and 

high-tech solar manufacturing jobs to these sites, including the placement of PV arrays that can reduce cleanup costs, building integrated solar 

energy systems as part of redevelopment, and solar manufacturing plants on brownfields.” For more information, see http://epa.gov/ and 

brownfields/partners/brightfd.htm.
35

Table B-6. State Policy and Incentive Comparisons: Massachusetts, North Carolina, and 

Colorado22

MASSACHUSETTS

Incentive Specifics Sector

New Generation Energy - Community 

Solar Lending Program

$5,000–$100,000 Private

Massachusetts DOER - Solar 

Renewable Energy Credits (SRECs)

$300–$600 (per MWh) Both

Mass Energy Consumers Alliance -

Renewable Energy Certificate Incentive

Both

Renewable Energy Property Tax 

Exemption

100% exemption for 20 years Private

CEC - Commonwealth Solar II Rebates $5,500 (per host customer), up to 

$250,000 per parent company

Both

CEC - Commonwealth Solar Stimulus $162,500 per project (up to $1 million 

for any host customer entity or parent 

company/organization)

Both

Policy Specifics Sector

Massachusetts - Net Metering Both

Renewable Energy Trust Fund Public benefit fund (PBF) Private

RPS In-state PV: mandated target of 400 

MW

NORTH CAROLINA

Incentive Specifics Sector

Renewable Energy Tax Credit 

(Corporate)

35% or $2.5 million per installation Private

Local Option - Revolving Loan Program 

for Renewable Energy and Energy 

Efficiency

Interest rate can be no more than 8% Private

Local Option - Clean Energy Financing Debt repaid via property assessment Private

Renewable Energy Tax Credit 

(Personal)

35% or $2.5 million per installation Private

NC GreenPower Production Incentive Payments contingent on program success Both

Progress Energy Carolinas - SunSense 

Commercial PV Incentive Program

$0.18/kWh for 20 years Both

TVA - Generation Partners Program $1,000 plus $0.12/kWh above the retail 

rate for solar and $0.03/kWh above the 

retail rate for all other eligible 

renewables

Private

Property Tax Abatement for Solar 

Electric Systems

80% of appraised value Both

North Carolina Green Business Fund Grant varies Both

Energy Improvement Loan Program 

(EILP)

State Loan Program $500,000 

maximum

Both

 22 DSIRE. http://www.dsireusa.org/. Accessed September 2010.
36

Policy Specifics Sector

North Carolina - Net Metering

Renewable Energy and Energy 

Efficiency Portfolio Standard

Solar: 0.2% by 2018

COLORADO

Incentive Specifics Sector

Boulder County - ClimateSmart Loan 

Program

Commercial: $3,000–$210,000 Private

Local Option - Improvement Districts for 

Energy Efficiency and Renewable 

Energy Improvements

Debt repaid via property assessment Both

Renewable Energy Property Tax 

Assessment

Varies Private

Boulder - Solar Sales and Use Tax 

Rebate

15% refund on sales and use tax for the 

solar installation

Private

Local Option - Sales and Use Tax 

Exemption for Renewable Energy 

Systems

Varies Private

Sales and Use Tax Exemption for 

Renewable Energy Equipment

100% Both

New Energy Economic Development 

Grant Program

Competitive grant, Recovery Act funded Private

Xcel Energy - Solar*Rewards Program $2/DC-Watt with a maximum rebate of 

$200,000; REC payments will step 

down over time as certain megawatt

levels are reached for each system 

classification.

Private

Policy Specifics Sector

Colorado - Net Metering Private

Mandatory Green Power Option for 

Large Municipal Utilities

Allows retail customers the choice of 

supporting emerging renewable 

technologies

Both

Boulder - Climate Action Plan Fund PBF Private

Renewable Energy Standard Solar-electric (IOUs only): 4% of annual 

requirement (0.8% of sales in 2020); 

half of solar-electric requirement must 

be located on-site at customers' 

facilities

Solar, Wind, and Energy-Efficiency 

Access Laws
37

Table B-7. Key Policy Comparison for Subject States23

RPS Massachusetts North Carolina Colorado

Policy In Place Yes Yes Yes

Effective Date 4/1/02 2/29/08 12/1/04

Targets 15% by 2020 and an 

additional 1% each year 

thereafter; in-state PV 

mandated target of 400 

MW

12.5% of 2020 retail 

electricity sales by 2021 

with 0.2% from solar

20% by 2020; solarelectric: 4% of annual 

requirement

PBF Massachusetts North Carolina Colorado

Policy In Place Yes No City of Boulder only

Effective Date 3/1/98 N/A 4/1/07

Charge $0.0005 per kWh in 2003 

and in each following 

year

N/A Maximum tax rates for 

electricity customers:

Residential: 

$0.0049/kWh

Commercial: 

$0.0009/kWh

Industrial: $0.0003/kWh

NET METERING Massachusetts North Carolina Colorado

Policy In Place Yes Yes Yes

Effective Date 1982 10/20/05 7/2/06

System Capacity 2 MW for "Class III" 

systems; 1 MW for "Class 

II" systems; 60 kW for 

"Class I" systems

1 MW 120% of the customer's 

average annual 

consumption

REC Ownership Customer owns RECs Utility owns RECs 

(unless customer 

chooses to net meter 

under an unfavorable 

demand tariff)

Customer owns RECs 

(must be relinquished to 

utility for 20 years in 

exchange for incentives)

TAX INCENTIVES 

APPLICABLE TO PV

Incentives

Massachusetts North Carolina Colorado

Property – 100% 

exemption for 20 years

Corporate – 35%

Property – 85% of 

appraised value

Property – Amount 

varies depending on rate 

set annually by the 

Division of Property 

Taxation

Effective Date 1984 Corporate 1/1/09

Property 7/1/08

2001

 23 DSIRE. http://www.dsireusa.org/. Accessed September 2010.