# Presentation: 048350

## Planning Bioenergy Options: Climate Feedbacks and Information Needs

- Robin L. Graham
- Oak Ridge National Laboratory
- November 15, 2006
- Climate Science in Support of Decision Making
- Session 4 Breakout:
- Energy Management and Planning: Application of Climate Science

## Bioenergy background

**Feedstocks**
-  Forest residue
-  Black liquor
-  Ag residues
-  Grains
-  corn/soybeans/rapeseed
-  Urban wastes
-   MSW, wood, cooking grease
-  Energy crops
-  grasses
-  trees

**Energy forms**
-  Heat
-  Power
-  Fuels
-  ethanol
-  biodiesel
-  hydrogen

## Bioenergy use

**Coal**
**23.6 EJ**

**Nat gas**
**24.8 EJ**

**Oil**
**42.8 EJ**

**Nuke.**
**8.7EJ**

**Hydro**
**2.9 EJ**

**Bio**
**3.0 EJ**

**Renew**

**Oil**
**162 EJ**

**Nat gas**
**99 EJ**

**Coal**
**101 EJ**

**Renew.**

**Hydro**
**27 EJ**

**Bio**
**Fuelwood**
**55 EJ**

**70% wood**
**20% wastes**
**10% EtOH**

- _Current_

- _Future??_

**Modern renewables**
** ****other than hydro**
**6 EJ**

- 2030 Goal – US Biomass R&D Act of 2000
-   4 EJ power & heat
-   8 EJ fuels
-   28 Tg of bio-based chemicals

- World estimates of technical bioenergy potential based on IPCC land–use scenarios *(M. Hoojwijk et al. 2005)*

|  | 2000
all | 2050
Biobased | 2100
biobased |
| --- | --- | --- | --- |
| Electricity
(PWh/yr) | 15 | 63-132 | 98-225 |
| Liquid Fuels (EJ/yr) | 142 | 171-361 | 217-613 |

**Notes:**
Note- Most of US bio mass is wood  and is used in the wood products industry for heat
Virtually all the US ethanol comes from corn – 13% of the US corn harvest goes to ethanol; we produce 3billion Gal/yr; ethanol production is rapidly rising due to subsidies, substitution for MTBE as an gasoline oxygenate. In 1995 we produced ~ 1 billion gallons so its tripled in the last 10 years. None the less US used 136 billion gallons of gasoline. 

Biodiesel is usually created from Soy oil and methanol and it represents very small fraction of fuel use in the US. only ~36 million gallons in 2004.  While regular diesel was 40.7 billion gallons.

World-
Fuel wood is still an very important source of energy in much of the world and estimates of fuel wood use range from 45 to 55 EJ/year. In contrast modern renewables ( electricity/biodiesel/wind/ethanol ) represent only 6 EJ

## Bioenergy           Climate

- Reducing GHG emissions by displacing fossil fuels
- Sequestering CO2 in soils
- Changing land surface albedo ?

## Quantifying greenhouse gas benefits from displacing Fossil Fuels Net bioenergy emissions- net fossil fuel emissions = Benefit 

- Bioenergy GHG benefit  depends on
- 	Energy type – transport fuel, electricity, heat
- 	Fossil fuel – coal, natural gas, oil
-   Technologies used to create both the fossil and bio-based energy.
- Challenging because a single feedstock e.g. maize will be merchandized into many products  - EtOH, protein, oil, starch, etc.
- Need to take a _life cycle approach_ – e.g., from well to tailpipe or bare field to transmission line.
-  Comparison done based on appropriate fuel unit- Net emissions/mile driven or kWh or MBtu heat or ha in production.
*Controversy over GHG benefits of bioenergy comes from how the system boundaries were drawn to do the analysis*

## GHG benefits=f(Source of feedstock) 

- Life cycle analysis of  GHG using a hectare of land for
- No till corn grain & soybeans production to produce starch-based EtOH * biodiesel
- Continuous no till corn grain production to produce starch-based EtOH
-  Continuous no-till corn w/50% stover removal to produce cellulosic & starch-based EtOH
- Continuous no-till corn w/70% stover removal  and a winter wheat cover crop to produce cellulosic & starch-based EtOH

- Kim & Dale 2005. Life cycle assessment of various cropping systems utilized for producing biofuels:bioethanol & biodiesel. *Biomass and Bioenergy* ( in press)

- Includes carbon sequestration

## GHG benefits = f(bioenergy technology and competing fossil fuels)

*Greene et al. 2004 Growing Energy: How Biofuels can help end America’s Oil Dependence. Natural Resource Defense Council*

## Bioenergy & C sequestration & albedo changes

- CO

- 2

**Conversion**
**to Hydrogen**

**CO****2**

**H****2**

- and sequester the CO2

- Bioenergy & C sequestration & albedo changes

- Production of biofeedstock can sequester or deplete soil carbon depending on land management ( energy crops vs. ag residue removal)
- Bioenergy linked to geologic sequestration could actually reduce atmospheric CO2 concentrations
- Power/heat production
- H2 production
- Decrease in albedo if woody energycrop replaces herbaceous cover in a region with snow cover.

- West & Marland 2005 personal communication

## Climate           Bioenergy?

- EJ Bioenergy is function of
- Plant productivity/yield (Mg/ha/yr)
- Magnitude
- Temporal variation
- Land availability (ha)
- Demand for food & feed
- Demand for fiber
- Demand for conservation/biodiversity
- Demand for energy
- Conversion efficiency ( EJ/Tg)

*Obvious Climate impacts  but not so easy to quantify*

## What do we think we know about climate impacts?

- Yield- Applicable to energy crops and ag residues
- Expected to go up in most of N. America due to CO2 and technology
- Yield will go down in some places largely due to drought ( e.g. Subsaharan Africa)
- Secondary impacts on productivity (disease & pests) are largely unknown but expected to be negative
- Assume energy crop yields will increase like historic ag crop yields have increased ( 1-1.5%/yr) due to technology
- C4 plants will respond less to CO2 increase
- Yield variability may increase with increasing climate variability
- Land area available for energy crops
- Most bioenergy potential studies don’t factor in land-use competition (Hoogwijk et al. 2003)
- Complex as it’s a function of climate change, population, food crop yields, technology assumptions
- Will increase in temperate latitudes; decrease in tropical

## Direct Climate change effects on Ag Yield – U.S.

**Climate Change Impacts in the United States t*****he Potential Consequences of climate Variability and Change*****By the National Assessment Synthesis Team, US Global Change Research Program****Published in 2000**

- Bioenergy needs stable yields

**Notes:**
Taking a global perspective, Agricultural production has winners and losers. Globally Agricultural production is expected to increase but there will be greater increases in developed countries and actual losses in many developing countries. ( Fischer 2002.. IAASA report... Lal 2005)

## Planning Bio-energy Options-Information needs

- Hoogwijk et al. 2005 Potential of biomass energy out to 2100, for four IPCC SRES land-use scenarios. Biomass and Bioenergy, 29:225-257

## Relevant CCSP research

- _Ecosystems – (Yield)_
- Potential consequences of global change for ecological systems – productivity, disturbance
- _Land use/Land-cover Change (Land availability)_
- Drivers of land-use and land-cover (LULC) change
- Future patterns of LULC
- _Human Contributions and Responses to Environmental change (Demand)_
- Changes in energy demand
- Changes in diet and fiber demand
- Changes in population and location of population
- _Technology adoption_

- And of course predicting climate