ALTERNATIVE ENGERY CHOICES TODAY

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ALTERNATIVE ENGERY CHOICES TODAY

Current ‘Green’ Alternatives	Advantages	Concerns
Solar Photovoltaic Cells absorb solar energy and convert it into electricity, via an electro-chemical process.	Inexhaustible energy source No fuel input or emissions output. Federal & State incentives – tax credits.	Expensive materials & installations – Well over ten years for payback without tax-payer subsidies. Weather dependent – Little to no energy available when cloudy, raining, or snowing. Only available during daytime hours – Requires expensive battery storage or shut down entirely without sunshine. Sensitive to location – requires large surface area. Low efficiency and energy conversion rates. Typically fixed in only one direction. Location is critical when tied into grid. DC to AC conversion required – Reduces efficiency and adds cost. Usually require very expensive batteries – To cover the gaps when sun isn’t shining and without grid connection.
Solar Thermal – A fluid absorbs solar energy in a collector, then transfers it into usable heat energy.	Inexhaustible energy source Very simple – Even do-it-yourselfers can install. No fuel input or emissions output. Federal & State incentives – tax credits.	Relatively high Installation cost Weather dependent – Little to no energy available when cloudy, raining, or snowing. Only available during daytime hours – Requires expensive battery storage or shut down entirely without sunshine. Sensitive to location – requires large surface area. Low efficiency and energy conversion rates. Typically fixed in only one direction.
Wind – Air turns rotors that generate electricity. Often installed in large groups called wind farms.	Simple, uncomplicated. Widely distributed, decentralized, international. High cost is coming down steadily. Runs continuously when wind is blowing. No fuel input or emissions output. Federal & State incentives.	Many turbines are needed to generate significant power. Turbines create noise, interrupt our landscapes, and interfere with agriculture, birds/bats/wildlife, and potentially emergency aviation needs. Wind is unpredictable, creating problems with load forecasting. Non-continuous – requires some sort of backup source. Difficult and expensive to connect with transmission lines. Supply can’t keep up with demand. Survives economically only because of government incentives – High cost won’t allow it to stand on its own.
Geothermal – Tapping the Earth’s heat for thermal energy or as steam to turn a generating turbine. Can be done in fairly shallow installations for buildings… or very deep to gather high heat for power generation.	Nearly inexhaustible source. Very predictable. Widely available to decentralized application. No fuel input or emissions output. Federal & State incentives. Economics can be better than solar or wind.	System for a building can be quite costly. Location is difficult due to depth of drilling. Plant eval‎uation is long and expensive. Deep structure conditions can change – sometimes requiring new drilling or total relocation. Unwanted gasses can leak to surface. Few contractors understand residential installations and are willing to service these systems. Paybacks are not good…without incentives.
Wave/tidal – Predictable water movement cycles piston generators.	Nearly Inexhaustible energy source No fuel input or emissions output. Federal & State incentives – tax credits. Visually out of sight – long way from land. Plenty of room – not infringing on people’s property.	Still largely unproven – Innovations are recent. Quite costly – Paybacks are long without government incentives. Must be location specific – Wave height and generator depth are critical. Tidal generating locations are even more difficult – requiring a natural means to trap the rushing waters. High maintenance costs. Subject to severe weather conditions.
Hydro-electric – Stored water in a reservoir flows past a generator turbine at the base of a dam.	Nearly Inexhaustible energy source No fuel input or emissions output. Established for many decades. Cheapest form of renewable energy.	Infringing on local property. Subject to weather extremes – drought and floods. Heavy environmental regulations make recent approvals nearly non-existent. Requires fast moving and heavy water volumes – Best locations developed long ago. Can endanger fragile fish or wildlife species. Requirestransmission grid to connect.
Ethanol - Gasoline additive fermented from corn, sugar cane, sugar beets, grasses, grains, agricultural waste, algae, or woody biomass.	Renewable – Based on plant sugars, and can be re-grown year after year. Local economic support – Produced locally and the money benefits regional economy.	Economically unstable – This industry survives only because of generous federal subsidies. When these are eventually reduced or removed, the entire industry is on very shaky ground. It’s also subject to the commodity price of its own feedstock, which greatly influences margins and retail pricing. Competes with food sources – Makes corn more scarce and expensive. Inflation trickles down into numerous related food products, across many sectors. Requires major commitment – To make a significant impact in our energy independence, we would have to commit far more land and resources than we could afford. We’re unlikely to see more than 20% of our total transportation fuel be produced in ethanol and even this would come at a very high price. Not Carbon neutral – Even though the combustion surrenders the same amount of CO2 that it absorbed during its growth, it typically requires more energy and fertilizer to grow, harvest, distill, and transport the fuel adding to, and not reducing its carbon footprint. Land and energy consumption to produce – Large amounts of farmland, energy, and labor are needed to plant, fertilize, harvest, transport, process, and transport again. Many reputable economists have calculated that corn ethanol production actually costs more to grow and produce than it benefits or returns back to the economy. Reduced vehicle mileage – Mileage is reduced, because the energy ratio is roughly 70% that of gasoline. Corrosive – Tends to deteriorate non-synthetic, natural rubber, and some metallic fuel system parts.
Biodiesel - Liquid fuel produced from natural oils, like soybean oil, for use in diesel engines.	Same as Ethanol, plus: Cleaner burning – than regular diesel fuel, with substantially fewer harmful emissions. Degrades naturally. Contains natural lubricants – to extend engine life. And it even smells like fried food.	Unless recycled from waste oil, same disadvantages as Ethanol, plus: Limited availability – Distribution links are still developing. Higher levels of NOx – nitrous oxide, a greenhouse gas, as it is combusted. Reduced flow ability – at cold temperatures. Storage tanks and lines should be insulation wrapped. Reduced vehicle mileage – Mileage is reduced, because the energy ratio is roughly 89% that of diesel fuel. Higher retail price – than regular diesel fuel, in most parts of the US.
Compressed Natural Gas – NG from common supply line is compressed into tanks for vehicle fuel.	NG is domestically produced – Not directly subject to OPEC or international pressures. Fewer harmful emissions – Cut by more than 50% overall. Cheaper than gasoline – The miles-per-gallon gasoline equivalent is lower. Anyone can participate – If you have NG at your home, and install a compressor station. Quieter engine – Combustion is much smoother. Tax incentives – Federal tax breaks to convert existing car or buy new.	Limited vehicle availability – A conversion kit must be EPA certified, and there are only a limited number approved so far. Efforts need to be greatly increased. Costly conversion – Even with incentives, the payback is many years out for an initial investment. Limited range – A tank of compressed gas lasts only so long. Distribution links are still scarce – Not enough CNG vehicles yet to justify a lot of refueling stations. Handling compressed gas – Full bottles are very heavy and very vulnerable. Tanks take up valuable space – Passenger/cargo space is sometimes reduced.
Woody Biomass – Chips, firewood, energy crops, sawdust, recycled pallets burned for thermal energy or electricity generation.	Uses materials that would otherwise be wasted. Best use of feedstock. Supported with government incentives. Recycles CO2 that was captured through plant’s lifetime – Ecologically sound practice. Energy crops have huge potential. Local source – money stays in community. In huge demand by coal-fired plants.	Construction downturn makes for much less availability from lumbering. High competition for limited supply pushes prices up. Problems with vermin, bugs, mildew, mold, and spontaneous combustion in storage. Transportation costs further limit affordability and range.
Agricultural Biomass – Waste from corn, beans, waste, oats or other energy crops burned for thermal energy or electricity generation.	Uses materials that would otherwise be wasted. Best use of feedstock. Supported with government incentives. Recycles CO2 that was captured through plant’s lifetime – Ecologically sound practice. Energy crops have huge potential. Local source – money stays in community. Same as Woody Biomass	Supply is subject to weather conditions. Price is subject to weather conditions. High competition for limited supply pushes prices up – ethanol and bio-diesel industries seek the same products and waste. Problems with vermin, bugs, mildew, mold, and spontaneous combustion in storage. Transportation costs further limit affordability and range.
Industrial Biomass or Refuse Derived Fuel – Paper, cardboard, sorted landfill waste, plastics, or processed human waste burned for thermal energy or electricity generation.	Uses materials that would otherwise be used for a lesser cause, like recycling. Supported with government incentives. Local source – money stays in community. Keeps nasty stuff out of landfills.	Problems with vermin, bugs, mildew, mold, and spontaneous combustion in storage. Transportation costs further limit affordability and range. Handling this can be a very messy process and under much more strict regulations. Combustion of fuel causes concerns with many industrial or utility burning systems.
Pellets or Briquettes – Chipped or pulverized biomass is re-densified to provide a drier, more consistent fuel.	Consistency – All the pieces are of a similar size, weight, and density. Low moisture content – Moisture content is typically less than 10%. Detoxification – Nasty contaminants are destroyed in the high-heat densification process. Transportation, storage, and handling – without bugs, vermin, decay, mildew, mold, combustion, or freezing. Better burning and higher efficiency – Burner system achieves maximum efficiency.	Adds significant extra cost – Hard to justify in many cases, over the price of loose biomass. Too small or too large – Boilers or furnaces can be finicky, as they were designed to burn a specific fuel, usually coal, and at a specific size. Briquettes may need to be crushed, like coal. Uncertain supply – Before a long-term commitment, a utility or industry must be certain that this processed fuel is available in ample supply, long-term. And there are few locations with more than 10 or 20 thousand tons of waste available annually.
Anaerobic Digestion - Microorganisms break down organic material in an oxygen-free environment, producing combustible gas.	Reduces odors and flies. Suitable for large operations. Maximizes effluent fertilizer efficiencies. State and federal incentives – tax credits.	Requires constant management, maintenance, and additional chemical treatments. Lower temperatures decrease efficiency. Very expensive – Would not do well economically without government incentives. Requires large volumes of waste – to make appreciable amount of energy.

The following initiatives do not necessarily address how we ‘produce’ our primary energy but deserve to be mentioned as they change the way we ‘consume’ energy and therefore have the potential to change the way our primary energy mix and carbon footprint will evolve.

Other widely discussed alternatives	Advantage	Concerns
Electric Vehicles – Using electricity as the primary propulsion fuel. Hybrids store electricity as a secondary fuel.	No harmful emissions – At least none while it’s moving. High efficiency – Converts all power sources without need for multiple gears or torque converters. Quiet Operation – Much less noise and vibration. Fuel produced locally – Money circulates regionally. Affordable recharging -Minimal costs, equivalent to less than $1/gal.	Limited range between recharging – This is why hybrids are so popular…to extend the range. Relatively long recharging – Compared to quick refueling of gasoline vehicles. Electricity generated from fossil fuel sources – Using grid electricity negates the efficiency advantages of electric vehicles. High cost – These vehicles are still very costly for the average consumer
Battery charging concepts – Initiatives like “Better Place” www.betterplace.com suggest recharging stations for electric vehicles in metropolitan areas and battery ‘swapping’ stations in rural areas.	Extended range – Electric vehicles will have more widely available opportunity to recharge Standardization – If electric vehicles would have a range of ‘standardized’ batteries, it would eventually be possible to ‘swap’ depleted units even in rural areas with fully recharged units and theoretically eliminate the need to ‘wait’ for a recharge.	Exorbitant cost – The development of a widely available network of charging stations for parked electric cars would cost hundreds of billions. Not practical – Although it may find some isolated adoption in some niche markets, it may be impractical to compete over parking spots at the station, or power kiosk, then secure a recharging cable (in inclement weather), leaving it charge the owners vehicle, but also their designated bank account with hefty KWH fees. These will be necessary to recuperate the huge capital investment. And the power will still be generated from fossil fuel sources in most areas. Technical challenges – Assuring safety and reliability for such potent recharging stations is still uncertain, without prohibitively high capital investment. It may be feasible in certain municipalities in conjunction with tax-payer subsidies, but a US-wide network is very improbable. Outdated concept – New emerging power-generating technology will make recharging of electric vehicles obsolete before the charging stations will even leave their infant stage. Mobile Magnetic power generators will very soon supply electric cars with an inexhaustible charge, eliminating any need for plug-ins. It’s like trying to cover the country with thousands of coal piles for steam cars in the early 1900s, when much more advanced combustion engines were soon to become widely available. However, utilization of recharging stations, during a transitional period, could be effective in a ‘reverse’ way modified to supply peak power to struggling utilities…known as Vehicle-to-Grid (V2G) once our technology has proliferated.
Hydrogen – Conventionally combined with oxygen in a fuel cell to produce electricity, or compressed as fuel for vehicles. See also – Fuel Cells	Increased mileage – Up to 50% better with the right mixture formula. Quieter engine – Combustion is much smoother. Tax incentives – Federal tax breaks to convert existing car or buy new. Improved engine performance – Longer engine life, less maintenance, cleaner exhaust. Renewable – Hydrogen is virtually inexhaustible with certain conversion systems. Environmentally friendly – The emissions are minimal and will help to clean up our air quality.	Sub-freezing weather – Fuels cells don’t do well when the water they depend upon starts to freeze. Hydrogen production is not earth-friendly – It involves oil and coal processing, and CO2 off-gassing. High investment required – Billions are required to build infrastructure. Some estimate as much as $5,000 per every vehicle. Cheaper and equally effective options are available. Distribution links are scarce – Not enough H-Vehicles yet to justify a lot of refueling stations. Handling compressed gas – Full bottles are very heavy and very vulnerable. Durability – Fuel cells are quite fragile & can be very finicky. Limited Range – A fuel bottle will only last so long.
Fuel Cells – Converts hydrogen and oxygen into electricity via a chemical process. Similar to battery without recharging. See also – Hydrogen.	Energy efficient and emits few pollutants. Flexible for many diversified applications. Decentralized for homes and business applications. Silent – Vibration free. Scalable and stackable.	Expensive compared to other options – Payback is distant. Still largely unproven for various applications…higher risk. Questionable reliability and durability.