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This comprehensive guide explores various energy sources - biofuels, hydrogen, electric vehicles, renewables, nuclear, and fossil fuels - in terms of efficiency, environmental impact, and economic viability. Delve into the complexities of energy solutions amidst climate change, national security concerns, and economic factors. Gain insights on transportation alternatives, net energy analysis, technological advancements, and the importance of transitioning towards cleaner, reliable energy sources. Explore the potential of renewables like solar, wind, and biomass, alongside challenges in nuclear energy and fossil fuel usage. Discover key considerations for a sustainable energy future in a world striving for energy security and environmental preservation.
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The Energy Construct Ben Cipiti May 1, 2008 Mid-Town Brews
The Energy Challenge • Climate Change We need clean sources of energy. • National Security We need domestic sources of fuel. • Economics We need alternative energy sources that can compete. • Acceptability We need to compromise on solutions. • Reliability We need to continue to maintain the integrity of the grid.
Transportation Alternatives Biofuels Hydrogen Electric Vehicles Alternative transportation technologies have been driven more by hype than science and engineering. We need more awareness about how these technologies compare, and we need politicians that understand the differences.
Biofuels • Net Energy Analysis • Shows that it takes about as much energy to produce the fuel as the amount of energy we can get out of it (ethanol and biodiesel)—energy inputs from fertilizer, harvesting equipment, transportation, conversion. • Interestingly, the energy inputs are mostly from fossil fuels which means that biofuels produce just as much pollution as oil. • Land Requirements • Even converting the entire corn crop to ethanol will only displace about 15% of our oil use. • We need to question if it is right to displace food crops (which other countries depend on) to produce fuel for our trucks and SUVs. • Economics • The total subsidy on ethanol currently equates to about $0.89 a gallon.
Hydrogen • Technology • The methods for producing, transporting, and finally using the hydrogen in fuel cells are 20-30 years away—we need solutions now. • It will take a massive infrastructure change to make the hydrogen economy work • Net Energy Analysis • The hydrogen economy is very inefficient for utilizing energy resources. • The overall efficiency is about 15%—meaning 85% of primary energy is wasted! Production: 45% Compression: 90% Distribution: 80% Fuel Cell: 50% Electric Motor: 90% 0.45 x 0.90 x 0.80 x 0.50 x 0.90 = 0.15 (15%)
Electric Vehicles • Technology • Batteries are the challenge—still need to reduce costs, increase cycle life, increase energy density, and achieve a rapid charge capability. • But…hybrids are providing a commercial channel for improving battery technology. Plug-in hybrids will be the next step. • Net Energy Analysis • The overall efficiency is about 30%—twice as much as with hydrogen. Production: 45% Transmission: 90% Battery Storage: 90% Electric Motor: 90% Battery Manufacturing: 90% 0.45 x 0.90 x 0.90 x 0.90 x 0.90 = 0.30 (30%) Environmental Concerns • Electric vehicles will only be as clean as our power generation portfolio…
Renewable Energy Solar Geothermal Hydroelectric & Ocean Biomass Wind Cost and reliability are still the key challenges of expanding renewable energy. All will continue to see small scale use. New venture capital money in these areas may provide the necessary innovation to push renewables to the next level.
Renewables in a Nutshell • Solar – expensive, low availability, will not expandsubstantially until significant cost reductions • Geothermal – reliability good, but limited sites, enhanced geothermal systems still expensive • Hydroelectric – limited sites, and environmental opposition • Ocean – technology still immature, but could make an impact longer term • Biomass – expensive on the large scale, large landrequirements, small scale uses make more sense (digesters) • Wind – costs are competitive in many areas, most likely to expand significantly, but reliability still an issue
Ohio Wind Resource Map • Class 4-5 wind resources (near the shore or off-shore) could provide electricity for 5-7 ¢/kWh. • Class 2-3 wind resources are less economic at closer to 8-10 ¢/kWh.
Nuclear Energy Fission Fusion The barriers to more nuclear power are political, not technical. Fusion continues to follow the “30-year rule” (fusion is always 30 years away).
Nuclear in a Nutshell • Fission – no greenhouse gas emission, the technology is economic (but political forces can change that), safety and reliability is proven, public acceptability is still an issue, need to decide on a solution for nuclear waste • Fusion – still requires extensive R&D, engineering constraints may never make fusion economic, safety and waste issues are not as rosy as proponents make it out to be
Fossil Energy Coal Natural Gas Oil For reasons spanning from climate change to national security to sustainability, we need to scale back on fossil fuel use. Developing economic carbon sequestration technologies will be a huge challenge.
Fossil in a Nutshell • Coal – most polluting power option, plenty of resources in the U.S., carbon sequestration will be costly but may be competitive with natural gas and renewables • Natural Gas – price volatility, limited U.S. resources, use should be reserved for home heating and for filling in for the low reliability of renewables • Oil – need alternatives to strengthen national security and our economy
Carbon Sequestration • Carbon capture technologies • Exhaust gases can be scrubbed with reagents or solids that absorb CO2—then the reagents are heated to drive off the CO2 for compression or liquefaction. • Membranes can be used for CO2 separation • Gases can be cooled to condense out CO2 • CO2 could react with Magnesium or calcium silicate to form carbonates • Algae for CO2 capture • Carbon sequestration technologies • Pumped into caverns or wells • Deep ocean sequestration • Direct disposal of solids or biomatter. • The energy required can drop the net efficiency of the power plant by 10-12 points, but IGCC technology may reduce that to as little as a 4 point drop—this leads to a higher cost of electricity.
What it Means for Ohio • Zero Emission Coal • With significant coal resources, Ohio is in a great position to push for carbon sequestration technologies. We need pilot projects, university collaborations, and public support to get the ball rolling on carbon capture. • Wind Energy • Wind is about the only renewable resource that makes sense for Ohio. The Lake Erie shoreline provides an incredible potential for both on-shore and off-shore wind farms. • Nuclear Energy • Ohio needs another energy option besides coal and wind. Nuclear is a proven and safe energy option that needs to be considered. Expansion at Davis Besse and Perry can occur in the near term, while green-field plants will take considerably longer to get built.