# Presentation: 582839

## Renewable Energy Overview

**July 18, 2007**

**Robert M. Neilson, Jr.**
**Renewable Energy & Power**

**Renewable Energy Overview**

## Electricity Generation

**Take Away Message:**
**All energy generation technologies have their advantages and disadvantages**
**What one chooses depends upon one’s needs and perceptions**

## Electricity Generation Technologies

**Petroleum**
**Coal**
**Natural Gas**
**Nuclear**
**Renewables**
**	****	****-  Biomass**
**	****	****-  Geothermal**
**	****	****-  Hydropower**
**	****	****-  Solar**
**	****	****-  Wind**

## U.S. Electricity Production (2005)

**U.S. Electricity Production (2005)**

- Renewable Sources

## Wind Energy Has A Long History

**The Egyptians used wind energy to sail on the Nile River in 2000 B.C.**

**The Chinese used vertical axis windmills to grind grain and pump water over 2,000 years ago**

## Wind Energy Has A Long History

**The French were the first to use the “classic” windmill in 1180**

**Windmills were widely used for pumping water in the settling of the American West**

## Wind Energy Has A Long History

**In the United States, the most notable early example of the use of a wind turbine to generate electricity was built by Charles Brush in Cleveland, Ohio in 1888**

## Wind Energy Has A Long History

**Today, wind turbines as large as 5 MW are used for generating electricity**

## What is the Origin of Wind?

**Global winds result from pressure differences across the earth’s surface due to the uneven heating of the earth by solar radiation**
**Spatial variations in heat transfer to the atmosphere result in pressure variations**
**Air moves from high to low pressure areas, creating wind**

## Local Wind Characteristics

**Local wind speed and direction are affected by a number of factors:**
**Temporal variations (annual, diurnal, short-term)**
**Terrain effects**
**Obstacles**
**Height above the ground**

## Wind Power is a Strong Function of Velocity

**	****        ****P = C****p********(1/2)********R****2****V****3**
**Where**
**C****p**** = power coefficient ****(ratio of rotor power to power in the wind)**
****** ****= mechanical drive train efficiency**
****** ****= air density**
**R = radius of rotor**
**V = wind velocity**

## Wind Power Classification

| Power Class | Wind Speed @ 50m, mph | Wind Speed @ 50m, m/s | Power Density, W/m2 | Resource Potential |
| --- | --- | --- | --- | --- |
| 2 | 12.5 – 14.3 | 5.6 – 6.4 | 200 - 300 | Marginal |
| 3 | 14.3 – 15.7 | 6.4 – 7.0 | 300 - 400 | Fair |
| 4 | 15.7 – 16.8 | 7.0 – 7.5 | 400 - 500 | Good |
| 5 | 16.8 – 17.9 | 7.5 – 8.0 | 500 - 600 | Excellent |
| 6 | 17.9 – 19.7 | 8.0 – 8.8 | 600 - 800 | Outstanding |
| 7 | >19.7  | >8.8 | >800 | Superb |

## Initial Area Wind Assessment

**Collect initial data from multiple sources (i.e., talk to people, look for existing data, wind maps, etc.)**
**Look at the lay of the land, prevailing wind direction, and vegetation (flagged trees, etc.)**
**Plan for collecting wind data (number, type, and height of instruments, cost, permits)**
**Quality wind data is important (people’s perception of “windy” is not good enough)**

## Does This Area Look Windy?

## Anemometer Tower Instruments

- Anemometer and Wind Vane

- Data Logger

## Anemometer Tower Installation

## Slide 17

## Idaho Anemometer Loan Program

**Program is administered by INL, IDWR-Energy Division, and BPA**
**State and private land**
**Data is available to the public**
_**[www.inl.gov/wind/idaho](http://www.inl.gov/wind/idaho)**_

##    Idaho Wind Map

-    Idaho Wind Map

## Wind Energy Comes in Different “Sizes”

## Wind Turbine Components

**Blades**
**Hub/Shaft**
**Gearbox**
**Generator**
**Yaw Control**
**Brake**
**Nacelle**
**Tower**
**Tower Foundation**

## LARGE TURBINE DIAGRAM

- BLADE

- HUB

- TOWER

- MAIN
- SHAFT

- MAIN
- BEARING

- NACELLE

- ANEMOMETER

- GENERATOR

- OIL COOLER

- GEAR BOX

## Wind Turbine Rotor Diameter

**Wind Turbine Rotor Diameter**

- 52 m (171 ft)

- 70.5 m (231 ft)

- 88 m (289 ft)

- 104 m (341 ft)

**850 kW**

- Rotor diameter

**1.5 MW**

**2.5 MW**

**3.6 MW**

**Boeing 747-400**

- Wingspan 64.4 m (211.5 ft)

- Length 70.7 m (231.9 ft)

## Why Is Utility-Scale Wind “Different”?

**Intermittent**
**Low capacity factor**
**Scheduling penalties**
**Remote (and location specific)**
**Constrained flow to major load centers**
**Low Energy Density (but “fuel” is free)**
**New**
**Not part of established processes**
**NIMBY**

## Wind Energy Environmental Impacts

**Air Emissions (None!)**
**Avian Issues**
**Visual Impact**
**Noise**
**Electromagnetic Interference**
**Land Use**
**Flora and Fauna**
**Safety**

## Air Emissions

|  | Emissions, kg/MW-hr  |  |  |
| --- | --- | --- | --- |
|  | CO2 | SOx | NOx |
| Wind | 0 | 0 | 0 |
| Coal
(conventional with controls) | 865 | 1.2 | 2.3 |
| Natural Gas
(conventional with controls) | 650 | 0.004 | 0.002 |

## Avian Impacts

**Bird kill has been an issue at Altamont Pass, CA**
**(Bats are a concern at some eastern sites)**
**Mitigation Concepts**
**Avoid migration corridors**
**Alternate tower designs (monolithic vs. lattice towers)**
**Fewer, larger turbines**
**Prey base management**
**Bury electrical lines**

## Visual Impact

**Modern Wind Turbines are Large!**
**Viewshed Alteration**
**Mitigation Concepts**
**Turbine placement (use landscape to advantage)**
**Design, number, and arrangement of turbines**
**Wind turbine color**
**Lighting**

## Wind Turbine Noise

**Aerodynamic noise**
**Mechanical noise**
**Noise from an operating wind farm is 35-45 dB(A) at 350 m (1,100 ft) – comparable to a refrigerator **
**Mitigation Concepts**
**Use of noise reducing blades and components**
**Distance from the observer**

## Electromagnetic Interference

**Wind turbines can interfere with television, radio, microwave, and radar transmission**
**Blade construction material, geometry, and rotational speed are important**
**Mitigation Concepts**
**Composite blades**
**Blade geometry should avoid sharp corners/edges**
**Avoid locating turbines in microwave communications paths and radar line-of-sight**

## Land Use Impacts

**Actual land required for turbines and access**
**On flat terrain, a wind farm requires about 60 acres per MW, but only 5% of the land is occupied by turbines, roads, and other equipment**
**On ridgelines (hilly terrain), a wind farm may require as little as 2 acres per MW**
**Land use compatibility**

## Flora and Fauna Impacts

**Reduction of habitat**
**Mitigation Concepts**
**Ecological survey**
**Avoid disturbing sensitive habitat (e.g., nesting areas)**

## Safety

**Blade Throw**
**Falling or Thrown Ice**
**Tower Failure**
**Attractive Nuisance**
**Mitigation Concepts**
**Distance to wind farm boundary**
**Prohibit maintenance during adverse conditions**
**Fencing**

## Economics of Wind Energy

**Generating Costs**
**Highly dependent upon wind resource characteristics**
**Capital cost**
**O&M costs**
**Financing cost**
**Avoided Costs**
**Fuel savings**

## Cost of Wind Energy

**COE =**

**Annual Energy Production**

_**(Capital Cost x FCR) + O&M Costs**_

- Where
**COE = Cost of Energy**
**FCR = Fixed Charge Rate (present value factor including ****	****debt and equity costs, taxes, and insurance)**
**O&M = Annual Operations and Maintenance costs**

**Cost of Energy is about $0.04 – $0.08 per kWh**

**Note:  Cost does not equal Price**

## Installed U.S. Wind Power Capacity

**Installed Capacity, MW**

- Year

**(1981 through 2006)**

## Federal Incentives 

**Renewable Energy Production Credit (PTC)**
**1.9 cent/kWh tax credit (first 10 yrs of operation)**
**Public Utility Regulatory and Policy Act (PURPA)**
**Required utilities to purchase power from independent generators for “avoided cost”**
**Federal Purchase Requirement**
**Sets renewable energy purchase requirements for electric energy consumed by the Federal government (not less than 3% 2007-09; 5% 2010-2012; 7.5% 2013 and thereafter)**

## Other Incentive Strategies

**Renewable Portfolio Standard (RPS)**
**Renewable Energy Credits (REC)**
**System Benefit Charge**
**Green Pricing/Green Tags**
**Emission Credits/Carbon Tax**
**Interconnection, Transmission, and Distribution Rules**

## You Know Why and What, but How?

**DEVELOPING WIND RESOURCES:**
**Prospect**
**Collect anemometer data**
**Analyze wind data**
**Resolve permitting and legal issues **
**Obtain electrical interconnection study**
**Obtain Power Purchase agreement**
**Arrange financing**
**Build and operate a wind farm**
**TOTAL TIME, start to finish**
**Three to five years**

## Wind Energy Information Sources

**WIND**
**U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy**
** **_**[www.eere.energy.gov/windandhydro](http://www.eere.energy.gov/windandhydro)**_
**Idaho Department of Water Resources – Energy Division**
_**[www.idahowind.org](http://www.idahowind.org/)**_
**American Wind Energy Association**
_**[www.awea.org](http://www.awea.org/)**_
**OTHER RENEWABLES**
_**[www.energyforkeeps.org](http://www.energyforkeeps.org/)**_

## Characteristics of Different Resource Types

- From E3 Inc. Presentation to Idaho Legislative Subcommittees (Sept. 06)

| Resource Type | Gas Combined Cycle | Pulverized Coal Steam | Coal Gasification | Nuclear | Wind | Geothermal | Run-of-River Hydro | Solar/Ocean Wave/Tidal | Energy Efficiency |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Cost | Depends on Gas Prices | Low | Medium | High | Medium | Medium | Site-specific | High | Measure -Specific |
| Operations | Flexible | Baseload | Baseload | Baseload | Intermittent | Baseload | Intermittent | Intermittent | Measure -Specific |
| Fuel Price Variability | High | Medium | Medium | Low | Low | Low | Low | Low | Low |
| Environmental Impact | Medium | High | Medium | High | Low | Medium | Low | Low | Low or Net Positive |
| Economic Development | Small | Large | Large | Large | Medium | Medium | Small | Large | Large |

| “Need” for Incentives | Small | Small | Large | Large | Medium | Medium | Large | Large | Large |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |

## Utility-Scale Electricity Technology Characteristics

| 
Resource      Type | 
Gas Combined Cycle | 
Pulverized Coal Steam | 

Coal Gasification | 

Nuclear | 

Wind | 

Geothermal | 

Large Hydro | 
Run-of-River Hydro | 
Ocean Wave/
Tidal | 

Solar | 

Biomass | 
Energy Efficiency |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 
Capital Cost  |  |  |  |  |  |  |  |  |  |  |  |  |
| 
O & M Cost |  |  |  |  |  |  |  |  |  |  |  |  |
| 
Fuel Price Variability |  |  |  |  |  |  |  |  |  |  |  |  |
| 
Plant Operation |  |  |  |  |  |  |  |  |  |  |  |  |
| 
Environmental Impact |  |  |  |  |  |  |  |  |  |  |  |  |
| 
Economic Development
 |  |  |  |  |  |  |  |  |  |  |  |  |

| 
Need for Incentives |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |