I have a BP system from Home Depot. My GE time of use net meter was installed 9/9/07. I would like to know how to interpret the readings. They are as follows:
TOU KWh peak 49996. This has not changed since install.
Total KWh 50266. This has been gradually rising.

Your bill from the electric company should have meter reading instructions on it, or your providers website should have instructions. Does your inverter have a meter or "odometer" on it to show what it has produced ?

I will assume that your meter is either a PG&E E-7 TOU rate plan--or, at least, you have a simple two tier plan (peak and off-peak).

So, assuming your meter started with 50,000 kW for Peak and Total kWhours (mine was set this way when installed)...

Total Power is Today's Total reading - Last Months total reading:

50,266 - 50,000 = +266 kWhours total ("+" equals you generated consumed more than you used in this time period)

Peak power is Today's Peak reading - Last Months Peak reading:

49,996 - 50,000 = -4 kWhours total ("-" equals you generated more than you used in this time period)

Off Peak Power = This months total calculated power - this months Peak calculated power:

266 - (-4) = 264 kWhrs total off-peak power consumed...

How much power you have used altogether...

Total Power + Inverter Power for time period *example, today's inverter reads 6,000 kWhr lifetime total - last month reading of 5,500 kWhr = 500 kWhrs):

264 kWhrs + (example) 500 kWhrs (inverter) = 764 kWhrs consumed by home...

-Bill

Fixed--"+" is consumed (used more than generated); "-" is excess generated...

Are you sure it isn't the reverse, ie. I have consumed more power than I have produced since system installation? My meter is a GE KV2CS. This morning the Total kWh reading was 50305. Now after about 9.5 hours online and the meter running backwards all day it reads 50286. The sum total of my 3 invertors for today is ~33kWh. The meter has only been running for a week. The first four days were over 100 degrees so the A/C got used pretty heavily and I know my consumption was high on those days. Thanks.

Sorry,

You are correct... I had a typo in my cut and past as I rearranged everything to try and make it more clear...

50286 - 50305= - 19 kWhrs (excess generated during reading period)

-19 + 33 = 14 kWhrs (consumed by home during period)

Sounds like you have a good sized grid tied system there.

Of course, you realize that with TOU billing (if it is similar to mine), that you are charged only for off-peak and peak power used... The "Total Power" is not directly used in your billing.

Generally, your best bet is to reduce your power usage during your peak period (noon-6pm, Monday-Friday for my plan) to maximize your credits during the expensive power period, and consume power with optional loads during the off-peak periods.

For example, crank down the A/C in the morning, then turn it off from noon-6pm and let the house slowly warm... Of course, having a well insulated home with shaded windows/walls during the noon-6pm period would be a big help in preventing the home from overheating during the day (as well as avoiding electrical appliance use, cooking, and such that add heat to the home during the day--I even do this with the freezer--I have it set "extra cold" but connected through a timer that turns it off between noon-6pm M-F...).

Lastly, check your first bill very closely--My first bill (and apparently, many folks in our area had the same problem) was really confused--instead of crediting me for ~100 kWhrs generated with the meter change over--they billed me for ~900 kWhrs used for a week's worth of billing--My wife was not amused when we got a 10x normal electrical bill after our first 7 days of "solar" production...

Problem was that the billing computer assumed the meter reader made an error when the old meter was changed--was not programed to allow a meter to "spin backwards" while I was waiting for PG&E to install the new meter/solar billing plan...

If you have a tiered rate plan (where they charge you higher rates when you use more electricity), there may be some real confusing bills if you, for example generate more power than you use for peak, and consume more power during off peak--for PG&E (as near as I can understand), they have (in the past) massage the data so that generating 300 kWhr during your peak period is added to the 300 kWhrs you use during off peak--pushing you into the 600 kWhr billing tier--instead of a net zero bill... My usage is not that high--I am always under baseline usage, so I have not received any over baseline billing so I don't know for sure what is going on with PG&E (California)...

-Bill

I live in Fresno so I am on the same type of plan as you. I wondered if "precooling" the house with cheap, off-peak electricity would be advantageous. The idea of running the freezer on a timer is a really good one, too. Thanks.

You have to check your rate tiers, and winter/summer pricing... For me (baseline) summer pk/ofpk is $0.29/$0.09 per kWhr--so if I am going to use the power anyways--as long as the total off-peak kWhr used is less than 3x the peak usage--I am (probably) saving money.

http://www.pge.com/tariffs/ERS.SHTML#ERS

If you are in the ~1,000 kWhr per month range, your prices are $0.48/$0.27 per kWhr (for in the ~600-900 kWhr/month range)... So, it is still a 2:1 offpk/peak advantage.

However, things get strange when you have solar and tiered rates... Before you do too much in over cooling before noon, and off afternoon (other than flat out conserving), check and understand your billing (you should get a detailed 3 page statement + your normal pg&e bill in a separate envelope)... If you are way positive during peak power, and way negative in off-peak power--PG&E can play some weird games with the baseline rate adjustments (as I have heard).

-Bill