Hybrid Car – More Fun with Less Gas

SDG&E proposed purchase of excess power generated by grid tied systems

register ::  Login Password  :: Lost Password?
Posted by kzin on July 21, 2008, 4:34 pm

I recently spoke to a San Diego Gas and Electric representative and he
informed me that while they do not currently purchase excess power from grid
tied systems there is a bill being considered by the CPUC (California power
utilities commission?) that would make it legal for them to do so.

All the info he had status wise was that the bill exists.

Does anyone have any further info on this, or a pointer to such?  Perhaps
some details on what it contains, the general attitude of SDG&E towards it,
and an idea of when this would be passed if ever?

Mark Levin

Posted by Russ in San Diego on July 26, 2008, 6:30 pm

I would certainly be interested to hear more about this, too.

The amusing/sad thing is that SDG&E recently started offering a TOU
net-metering tariff that will essentially give me incentive to put
LESS power onto the grid.

That's because my PV system generates a slight excess of energy
annually.  The TOU plan raises the rate by around 10 cents/kWH during
summer peak hours (just when I'm pushing most of my power out to the
grid).  This means that my net excess will be that much greater.

Which means that when my wife wants a big TV or a freezer in the
garage, I might as well accommodate her, since SDG&E ain't gonna pay
me back for the excess.  And/or I can leave my gas furnace turned off
during the winter, and buy some of those nice electric heaters Costco
sells.  Heck, SDG&E won't even credit my net excess against my monthly
minimum -- which suggests that it would SAVE ME MONEY to ADD enough
load so that I'm eating at least 1 kWH per day during the non-summer
months!  Ain't that a kick in the pants?  I can SAVE money by USING
more power from the grid!  I should set up a nice fat load resistor in
my back yard.  8-)

SDG&E ought to:
a) credit net excess against monthly minimum payments;
b) pay wholesale rates for whatever excess is left after that

Doing this would give me incentive to keep our load low and push more
power to the grid.

Posted by daestrom on July 29, 2008, 12:33 am
 Russ in San Diego wrote:

So do they consider it 'excess' when the bill drops to zero, or 'excess'
when the total kWhr cross zero?

I can see where you could have a net positive usage but a negative bill with
those sorts of TOU rates.  Generate at high price and use at low price.  You
use more kwh than you generate, but the $$ goes the other way.


Posted by dold on July 29, 2008, 6:35 am
The Net Metering from PG&E is a dollar amount, with an annualized
reconciliation on the anniversary date of your installation.  There are
some fixed fees that you can't escape, and don't count against your
generated dollar amount, so the real point where you begin to lose out is
around $0 per year.

In individual months where my TOU billing amount and peak usage is below
zero, I still have a net usage.  

Clarence A Dold - Hidden Valley Lake, CA, USA  GPS: 38.8,-122.5

Posted by dold on July 28, 2008, 1:39 am
Currently, PG&E does have a plan that will pay for excess electricity, but
at wholesale rates for all the energy sold to them, retail for your
purchases.  For most residences, this is not a good deal.

There are quite a few vineyards in Napa/Sonoma area that do use this plan.

Recently, SunPowerGeo installed their first floating PV system, which will
generate excess energy, with PV modules floating on a pond, not taking up
valuable vineyard real estate, and reducing evaporation from the pond.

Clarence A Dold - Hidden Valley Lake, CA, USA  GPS: 38.8,-122.5

This Thread
Bookmark this thread:
  • Subject
  • Author
  • Date
please rate this thread