What is Alternative/Renewable Energy and Why is there a need for it?

The Current Situation:

Electricity Generation, Space Heating, Transportation dominate our uses of energy

Most traditional Energy production comes about via steam driven turbines so the heating of water is what is essential.

• Coal Fired Steam Plants
• Nuclear Fired Steam Plants
• Oil/Natural Gas Fired Steam Plants

Basic concept of alternative energy sources relates to issues of sustainability, renewability and pollution reduction Despite this, deliverable cost to the consumer still drives everything which becomes a large barrier.

In reality, Alternative Energy means any thing other than deriving energy via Fossil Fuel combustion. Since 90% of our current energy usage is derived from fossil fuels and since there is only 50--70 years of production left in that resource then there is a clear need to invest in alternative energy sources NOW not later.

Basic Barrier to all forms of alternative energy lies in high initial costs and long payback times. This is the fluourescent lightbulb syndrome on a much larger scale.

This can only be solved if we have a subsidy program that allows startup companies to have long pay back times. Possibly, the current move toward energy deregulation will create this kind of framework.

Currently we have no significant production line alternative energy source operating anywhere in the US. There are a few successful "demonstration" projects operating in California which could serve as prototypes.

The only regional examples of renewable resources for electrical energy generation are Hydropower in the Pacific NorthWest and the Tennessee Rivery Valley. Yet it is now highly unpopular to even consider building more dams, even though this is a proven renewable energy source.

Given the fact that the oil WILL run out then sensible choices which are not plauged by NIMBY, for profit only, and corporate lobbying must be made. Can we do this? In other words, our decision making process is so paralyzed by self-interest that its unclear any sensible large scale decision can be made.

Here are the choices where we must recognize that all form have both good and bad points.

Forms of Alternative Energy:

• Solar:
  Advantages: Always there; no pollution

  Disadvantages: Low efficiency (15%) which can only be compensated for by large collecting areas; significant generation of waste heat ; Very high initial costs; lack of adequate storage materials (batteries); High cost to the consumer although these costs are going down. Current levelized cost is 20-25 cents per KWH.

  Example:

  • A site in Eastern Oregon receives 300 watts per square meter of solar radiation averaged over the year.

  • The solar panels are 10% effecient and are illuminated, on average, 8 hours a day

  • To run your house you need about 100 KWHs per 24 hour period

    Given this information, how many square meters of solar panels do you need?

  • One square meter gives you 300 x 0.1 = 30 watts of Power.

  • Since you only collect sunlight, on average, for 8 hours then in one 24 hour period this square meter delivers 30 x 8 = 240 watt hours of energy = 0.24 KWHs per day

  • you require 100 KWHs per day so you need 100/.24 = 400 square meters.

• Hydro:
  Advantages: No pollution; Very high efficieny (80%); little waste heat; low cost per KWH (4.5 cents); can adjust KWH output to peak loads; recreation dollars

  Disadvantages: Fish are endangered species; Sediment buildup and dam failure; changes watershed characteristics; alters hydrological cycle

• Wind:
  Advantages: none on large scale; supplemental power in windy areas; best alternative for individual homeowner or a regional consortium. In SE Minnesota, Wind Energy is feed into the power grid and sold to the consumer for 4.5 cents per KWH.

  Disadvantages: Highly variable source; relatively low efficiency (30%); unasethetic (visual pollution); disruption of migratory birds (note this is what killed the recently proposed Columbia River Gorge wind turbine project).

• Geothermal:
  Advantages: very high efficiency; low initial costs since you already got steam

  Disadvantages: non-renewable (more is taken out than can be put in by nature); highly local resource (EWEB recently abandoned its proposed 10 MegaWatt Facility and Newberry Crater as the geothermal yield was lower than originally thought)

• Ocean Thermal Energy Conversion:
  Advantages: enormous energy flows; steady flow for decades; can be used on large scale; exploits natural temperature gradients in the ocean

  Disadvantages: Enormous engineering effort; Extremely high cost; Damage to coastal environments?

• Tidal Energy:
  Advantages: Steady source; energy extracted from the potential and kinetic energy of the earth-sun-moon system; can exploit bore tides for maximum efficiency Disadvantages: low duty cycle due to intermittent tidal flow; huge modification of coastal environment; very high costs for low duty cycle source

• Nuclear Fusion: Forget it, we aren't smart enough yet.

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