Heat Pump for Heating and AirConditioning in San Diego

Re: Heat Pump for Heating and AirConditioning in San Diego

Assuming San Diego's power policies are somewhat similar to our's in Northern California (PG&E)--Your meter will spin backwards during mid-day. And forwards at night.

The net result is read at the the end of the month.

For example, in summer, I will generate around 250 kWH a month from Noon-6pm Monday-Friday which I paid to my account at ~$0.30 per kWH ($75 credit)

My off peak usage will be 80 kWH @ $0.10 per kWH (call it $8 usage)

My net for summer will be $75-$8=$63 credit for summer month.

In the winter, my usage is more than my generation, so I pull from my "account" and only pay ~$6 per month minimum billing (I cannot avoid that charge).

At the end of the year, any "money" left in the account is reset to ZERO. If there is a negative balance, I have to pay the amount due.

If I have generated more kWH than I have used, I will get something like $0.05 per kWH for excess generated (zero to maybe $20 credit for me).

Note, it gets more complex because we have tiered billing. These tiers also apply to the credit amounts too. But it is not easy to calculate--and years ago, PG&E temporally changed the calculations which dramatically increased off peak power costs (i.e., generated power would push us into a higher billing rate, which dramatically increased our off-peak power costs--so on paper, a large solar array penalized people just like a large A/C system would--very mad customers until plan was changed back).

Make sure you understand the billing for your utility. In California, I believe you will have to have Time of Use Billing. If you have heavy power usage during working hours (10am-6pm roughly) for A/C or computer servers, etc.---And you have a "smaller" solar power system, it is possible that with TOU billing and a smaller array to actually end up paying a larger utility bill with solar vs your "no solar GT" bill. (This killed people that wanted to try a small system first to see how well it worked).

Also, if you pay commercial rates--The whole numbers game for GT Solar is a different kettle of fish. And much more difficult to justify in many cases.

Anyway--Do not assume anything. Ask questions and (if you are using an installer), have them show you what your billing will be (not always easy unless you have time of use logs for your home--should be available with the new "smart meters").

-Bill

In northern California, using a lot of power off peak will push us up into much higher tiered pricing... So be careful.

Total Energy Rates ($ per kWh) PEAK [B]OFF-PEAK [/B]
Summer 
Baseline Usage  $0.31312  ( )$0.07921 ( ) 
101% - 130% of Baseline  $0.33128  ( )[B]$0.09737[/B] ( ) 
131% - 200% of Baseline  $0.48086 (R) $0.24695 (R) 
201% - 300% of Baseline  $0.52086 (R) $0.28695 (R) 
Over 300% of Baseline  $0.52086 (R)[B] $0.28695[/B] (R) 

Winter   
Baseline Usage  $0.11093  ( )$0.08262 ( ) 
101% - 130% of Baseline  $0.12909  ( )[B]$0.10078[/B] ( ) 
131% - 200% of Baseline  $0.27867 (R) $0.25036 (R) 
201% - 300% of Baseline  $0.31867 (R) $0.29036 (R) 
Over 300% of Baseline  $0.31867 (R) [B]$0.29036[/B] (R)