[SGVLUG] Off-topic - US govt energy site - interesting statistics

Michael Proctor-Smith mproctor13 at gmail.com
Tue Jan 1 11:59:46 PST 2008


On Jan 1, 2008 12:16 AM, David Lawyer <dave at lafn.org> wrote:
> On Mon, Dec 31, 2007 at 12:57:27PM -0800, Stan Schwarz wrote:
> > > While the EIA has some significant data, I can't seem to find some of
> > > the most important data using this "homepage" url.  One important item
> > > is the thermal efficiency of generation electricity from fuel,
> > > expressed as an inverse of efficiency in BTU/kwh and known at the
> > > "heat rate".  In 1960 it was about 10,760 BTU/kwh and today it's not
> > > much better (10,400 +- BTU/kwh).  That's 45 years of stagnation in
> > > improving energy efficiency.  One reason: save $ on capital
> > > investment.
> >
> > It's my understanding from the energy lecture series here at
> > Caltech that the efficiency of converting heat to electricity
> > is about as efficient as it's ever going to get. There are
> > some fundamental thermodynamic limits on it. Steam turbine
> > technology is pretty mature, so it's about as close to the
> > theoretical limit as is possible.
>
> Yes but we are way below that limit because power plants have often
> chosen to save $ and buy less efficient plants.  The most efficient
> plant might use GE's turbines (H system):
> http://www.ge-energy.com/prod_serv/products/gas_turbines_cc/en/h_system/index.htm
> It claims that the turbine is 60% efficient which sounds too good to be
> true.  Well, elsewhere it claim that the one plant in actual
> operation is almost at 60%.  I'm wondering if this includes auxiliary
> power needed for feed-water pumps, etc.  And auxiliary power might be
> say 5% of generated power.  At any rate power plants are available at
> net efficiencies of well over the existing 33% average.
>
> Who is buying this GE turbine?  Nobody in the US.  Except GE is now
> installing one nearby S. of Riverside, which will be owned by GE.  If
> you can't sell them, use them yourself.  One reason for no sales is
> that this uses a combined cycle using natural gas, and natural gas
> prices have risen.
>
> The fact that power plants reject more costly but more efficient
> hardware may (or may not) result in energy savings, since a more
> costly system requires more energy to design and manufacture it.

Well it is not always the Power companies fault, sometimes it is the
local community that will not let the power company upgrade. Several
years ago when I lived in Morro Bay. For people that do not know there
is a power plant there, anyway then wanted to remove one three
original boiler, steam turbine pairs and build a new pair gas turbines
that recover waste heat to run a steam turbine. Which they were
claiming were 80% efficient as a system, replacing a system that had
never been upgraded and was so inefficient that they never used it.
But the not in my back yard crowd in the city blocked the
construction.


More information about the SGVLUG mailing list