CHARACTERISTICS

To reduce carbon emissions, non-carbon-based fuels like biomass, solar, wind and hydroelectricity can substitute for fossil fuels. In most cases, substitution would comprise shutting down the fossil plants or moving them down on the dispatch order as new non-carbon-based power plants begin operation. Biomass can substitute for or be blended with coal as a means of substitution.

Switching from carbon to non-carbon fuels directly reduces carbon emissions. In addition, most other air pollutants and many wastes would be greatly reduced since most renewable (non-carbon-emitting) technologies do not emit air or waste pollution.

However, switching from fossil to non-carbon sources can be expensive. In addition, many non-carbon-emitting technologies can produce power only on an intermittent basis–for example, when the sun shines or the wind blows. In addition, most non-carbon technologies are small in scale (kW renewable systems vs. multi-MW fossil fuel plants). Therefore massive numbers of units would be required to substitute non-carbon fuels for fossil fuels to achieve large carbon emission reductions.

SIZE:
< 100 MW

FEATURES:
Most renewable systems are small in scale and offer siting flexibility.

COST:
$0.05-0.25/kWh (renewables) vs. $0.02-0.10/kWh (fossil)

CURRENT USAGE:
In the U.S., 100 GW renewable fuel capacity, (of which 80 GW is hydro). The world market for renewable energy production systems is estimated at approximately $1 billion annually. Renewable energy use is rising all over the world, but most developing countries generate only 0.3% of electricity from renewable energy. Considerable new capacity using wind energy is being installed.

POTENTIAL USAGE:
In the U.S., resource potentials have been assessed at 9 GW of photovoltaics; 735 GW of wind

ISSUES ASSOCIATED WITH IMPLEMENTING ACTION

• In regions of rapidly growing power demand, replacement of carbon-emitting sources with non carbon-emitting sources may be impractical. However, non-carbon technologies could be used as additional power sources.
• The cost of non carbon-emitting power generation is likely to be considerably higher than from carbon-emitting sources.
• Most non-carbon emitting technologies produce power intermittently. Therefore power sources would have to be available for back-up power, to be used when the renewable sources are not producing power.
• The largest potential for most non carbon-emitting sources is far from current power demand centers requiring construction of new transmission systems–with the accompanying infrastructure costs and transmission losses.

CLIMATE CHANGE IMPACT

EMISSION EFFECT:
    

CONDITIONS FOR EMISSIONS MITIGATION:

• Low electric power demand growth.
• High value provided for clean power (green power).

EMISSION ESTIMATE:
No carbon emitted from these sources

COST-EFFECTIVENESS:
$21-400/ton carbon removed

SECONDARY EFFECTS:
Emits no SO₂, NO_x, or most other wastes

RESOURCES

• U.S. Department of Energy Office of Renewable Energy and Energy Efficiency hosts a website with links to all of its programs on renewable energy at http://www.eren.doe.gov.
• The Centre for the Analysis and Dissemination of Demonstrated Energy Technologies (CADDET) provides an on-line directory of technical reports and development status for renewable energy technologies. http://www.caddet-re.org/

CONTACTS

CADDET Centre for Renewable Energy
Mike Landy
ETSU
Harwell
Oxfordshire OX11 0RA
United Kingdom
Tel: + 44 1235 432719
Fax: + 44 1235 433595
caddet.renew@aeat.co.ukhttp://www.caddet-re.org

National Renewable Energy Laboratory
Golden, CO
Tel: (303) 275-3000
http://www.nrel.gov


U.S. Department of Energy
Office of Energy Efficiency and Renewable Energy
Washington, DC
Tel: (202) 586-8121
http://www.eren.doe.gov