|
OSA |
ALTERNATIVE ENERGY |
![]() |
1. Solar Power Overview
a. Solar power design analysis
2. Hydroelectric Overview
a. Hydroelectric design analysis
i) mini-hydroelectric design analysis
i) micro-hydroelectric design analysis
3. Wind Power Overview
a. Wind power design analysis
4. Biofuels Overview
a. Biofuel energetics calculations
b. Biofuel carbon footprint comparisons
c. Environmental and economic caveats of biofuel
As coal- and oil-fired power plants are coming under increasing scrutiny for their role in contributing to climate change, there is an increasing focus on the development and use of alternative energy sources that do not introduce carbon dioxide to the atmosphere and are therefore not environmentally unsustainable. In the growing comprehension of the combination of delicacy and robustness in the world's energy reserves, alternative energy refers to any power that does not require the combustion of hydrocarbons nor is dependent upon the nuclear fission reaction. While there are a great many niche forms of eclectic alternative power generation, the top three examples below encapsulate about 98% of the market share. Since these renewable resources are within the reach of households of relatively modest means, and certainly to communities acting collectively, these dispersed sources of small amounts of power will become increasingly important to national grids to contribute to the power generated by large-scale hydro, nuclear, and hydrocarbon power plants.
Solar Power is most familiar in the form of solar panels. Photo-voltaic panels are only one source of solar power generation, however. Solar concentrators use mirrors and lenses to achieve a source of heat with which to turn an alternator and is used for municipal-scale AC-Direct power generation. Photo-voltaic technology is also currently exploited in energy farms of about 2 megawatts per five acre parcel.
At the municipal scale of power generations, solar concentrators and large-scale photovoltaic must be connected to a grid. Since the power generated and converted to alternating current cannot be stored, large scale solar power generation requires connection to the grid since after dark the facility will require power from the grid generated by some other means.
However, with the use of batteries and an inverter, photovoltaic panels make possible self-sufficient residential scale power supply just from the area available on the roof. Such power supplies are likely in the near future to be much more common-place and not restricted to locations beyond the grid but include homes and businesses connected to the grid as well.
Small scale solar power generation is at some finite time-frame ALWAYS competitive economically with paying for grid power, no matter what the application is, residential or commercial. As oil prices--and energy prices in general--rise, solar and other alternative sources become increasingly cost competitive.
Hydroelectric power depends on the flow of water across relief. Pressurized water lines turn a turbine, which in turn turns an alternator to produce the current. Where hydroelectric is available it is commonly a superlative source of energy and competes favorably with all other options. Hydroelectric resources are not particularly abundant and are far trickier to capitalize upon than solar power. However, when you have it, you have it.
DC-power generation and the charging of batteries is the most efficient use of the resource and is called micro-hydro. AC-direct power generation requires more water and does not have any battery storage. It is best if such systems can be tied to the grid to sell power in excess, since any power not used in mini-hydroelectric applications must be burned off in heat.
Wind power becomes viable for residential scale turbine installation when the average wind speed exceed about 12 miles per hour. Like hydro, wind power can be harnessed as either a DC charging source that depends on a battery bank and AC-inversion, or as alternating current to be fed into a grid. Like solar, wind power is not adequate on its own because there are times when there is no wind just like at night there is no solar power. Without a grid that buys generated power back to offset the costs of purchasing power from the grid for consumption, AC-Direct wind generation is untenable. However, wherever favorable winds exist, wind power is typically one of the most efficient of the alternative power energy options. The only drawbacks are issues of aesthetics and a minor threat to birds.
Ethanol and biodiesel require considerable energetic investment just to yield the energetic payoff, and the returns of single-digit energy gains is not convincing as a significant economic alternative to conventional fossil fuels. Arguably at some degree of production efficiency, biofuels may have a potential to be environmentally sustainable. Possibly sugar-cane ethanol may meet that standard. But corn certainly does not and competes for food staples, acting as a source of imbalance in food markets. But beyond all those economic factors, biofuels still are just another form of fuel that produces carbon dioxide as an oxidation product and therefore contributes to climate change and is therefore by definition not environmentally sustainable, even if it might be labeled by an agricultural energy apologist as a renewable resource.
Home Mission Water Energy Sanitation Products Services Technical Reports Contact Inquiry