Comparative Review of Alternative Energies

Why the need for Alternative Energies?

Based on known oil reserves and the worldwide consumption rate, most estimates suggest this reserve has only 50 more years of production left in it its important that this is believed!

Clearly, environmental pollution is unavoidable so informed decisions must be made.

Forms of Pollution:

Global Impact of Sources of Energy Generation:

Air Pollution:

Normally the carbon content of fuels (which is high) oxidizes during the combustion process to form CO2 (carbon dioxide)

Incomplete combustion leads to the formation of CO:

2C + O2 --> 2CO

Sources of CO pollution: (million tons per year)

Automobiles dominate because the combustion of gasoline under conditions of high pressure is quite incomplete

Some Internet Resources on Pollution:

Pollution Prevention Home Page

For the future our choices are:

Every form of energy generation has environmental fall-out.

However, this basic fact continues to elude people who somehow thing some forms of energy generation are benign (only nuclear fusion is benign).

Most forms of alternative energy generation require much less of an organizational infrastructure. This means that a shift to alternative energies means a loss of jobs. This is undesirable to most politicians.

What happens if we try to be objective and evaluate our choices via some standard considerations, such as:

Evaluation Criteria for Alternative Energies:

Comparative Table

Evaluation

Solar Thermal

PV

Hydro

Wind

OTEC

Tidal

GEO

Biomass

Capital Costs

Large

Large

Enormous

Moderate

Enormous+

Enormous

Small

Small

Operating Costs

Moderate

Moderate

Neglegible

Small

Unknown

Neglegible

Small

Moderate

Efficiency

15%

5--10%

80%

42%

7% +

25%

100%

25%

Renewable

Yes

Yes

Yes

Erratic

Yes

Yes

NO

Maybe

Storage

Not Needed

Unclear

Built-IN

Essential

Not Needed

Unclear

Not Needed

Not Needed

Pollution

None Really

Waste Heat

None

Visual

None

None

Steam Plumes

Particulates; CO

Levelized Costs

25 cents KWH

16 cents KWH

4 cents KWH

4.5 cents KWH

Unknown

Unknown

Low

Unknown

Environmental Impact

Moderate

Large

Enormous

Small

Unknown

Outrageous

Small

Moderate

Large Scale

Too Expensive

Possible but Expensive

Proven already

Very Possible

The Solution

Discrete Locations

Discrete Locations

Net Energy Gain?

Small Scale

NO

Difficult

Low Head --> Legal

Definitely

NO

NO

NO

Absolutely

Unit Capacity

1000 MW

Depends on Acreage

2000-6000 MW

Highly Variable

As large as you need

250 MW

1000 MW

50-100 MW

Employment Opportunties

Few

Few

Few

Few

Lots to build it

Some

Few

Many

What about Energy Storage?

Options:

Bottom line(s):

Wind energy coupled with advanced battery design has real promise and that promise is now being turned into real implementation. Wind power does exist.

With the development of the Advanced Gas Turbine energy co-generation at biowaste facilities becomes possible. Moreover, the AGT provides a viable alternative to coal fire steam plants, using natural gas imported via pipeline from Canada. A local example will be on line in 2003.

OTEC provides a truly large scale solution but may be too expensive to ever implement what does this tell us about our priorities?

Solar PV does not look economically viable on the large scale. On the small scale, improvement in solar shingle technology is good for the consumer.

As of 2001 there remains little incentive to not look for new oil reserves. Just look at the price of gas at the pump it remains low.

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