Subject: Re: Wind and solar power

From: William R Stewart <[email-masked]>
Date: Mon, 27 May 1996 09:29:17 -0400

Craig Mohn wrote:
> 
> "Richard W. Tarara" <[email-masked]> wrote:
> 
> >A couple of comments about this (and station-car) thread.  One thing to
> >keep in mind is that eventually renewable energy source MUST replace the
> >'chemical' energy use such as gasoline, fuel oil, natural gas.  With
> >Electrical energy NOW only 14-16% of the total energy picture, the AMOUNT
> >of energy that the renewables will have to produce is staggering!  I had a
> >class do a project a few years ago of designing an energy system for the
> >U.S. in the year 2050 where only 50% of the energy could come from fossil
> >fuels.  We projected moderate population growth, a 25% overall inprovement
> >in energy efficiency,

This is one of the most significant areas of improvement for the economic
success of renewables. For some of the details, see;
       http://www.nrel.gov/documents/erec_fact_sheets/erec.html

- Lighting loads can be reduced by ~70% by use of compact fluorescent bulbs.

- Heating and cooling loads can be reduced dramatically (approaching 100% in some 
  instances) by many alternatives;
 
  - Passive/active solar heating and cooling
  - Evaporative cooling in low humidity areas (e.g., Southwest US)
  - Ground Source Heat Pumps
  - More effective use of insulation, weatherproofing and thermal storage
  - Landscaping: blocking cold north winds with evergreens on the north,
    and shading the house with decidous trees in the summer. (See above 
    reference for more info)

- Appliances are already undergoing signficant energy efficiency improvement, due
  in part to incentives from the US Department of Energy. 

- Hot water heating requirements can be lowered by use of solar hot water supplementing
  and through the use of heat rejection from ground source heat pumps in the summer.

Major improvements can be realized by implementing the above measures, especially moving
>from  electrical resistance heating to solar and/or ground source heat pump.

> >and a very slightly higher standard of living.  Most
> >groups chose to mix nuclear, wind, and solar but ended up with land usage
> >on the order of the area of New Hamphire

This can be dispersed by the use of rooftops, parking lots, and virtually any structure
that receives sunlight for the deployment of photovoltaic panels. 
http://ocaxp1.cc.oberlin.edu/~lwalter/photovoltaic.html

> > and cost estimates in the 10s of
> > TRILLIONS of dollars.

Costs for wind and solar energy have been decreasing every year.  For example,
solar photovoltaic costs have dropped an order of magnitude since the late
1970s.  The aformentioned energy efficiency improvements will also reduce this
cost estimate.  

> >50% of the TOTAL U.S. energy usage is a VERY LARGE
> >NUMBER (on the order of 100 or more times that provided by renewables
> >today!)  Anyway--the point is that the MAGNITUDE of our energy use MUST be
> >kept in mind along with the fact that today 95% of all energy is provided
> >by fossil fuels with most of the rest from nuclear and hydro.  

In the US, the 1994 breakout was:  

   Coal 31%, Gas 27%, Oil 23, Nuclear 10, Renewable 8%

   http://www.eia.doe.gov/neic/infocard.html

Cheers,

Will Stewart