I didn’t pay my electric bill last month and that’s something that will be very easy to get used to because this July bill had a credit of $28.15.

July was my first National Grid bill that encompassed a full month of solar panels on my roof. It appears, if I read my bill correctly, we produced 276 kilowatt hours (kWh) more than we used, which generated the $28.15 credit.

As I understand NG’s complex formula, I will get a check every quarter for power we send onto the grid. Update: Solar City from whom I lease the solar system says NG will never cut me a check. NG customer service said they would be happy to cut me a check – that I have a choice of check or credits toward non-sun time when I need its generation.  The latter will do for now.

I will need a full year to truly understand output an d the ins and out of billing. After all, summer provides the most hours of intense sunshine. Solar City system guarantees 7,000 plus kWh per year and it seems we are well on our way to beating that given, it has produced 1,800 kWh in two months.

My net meter read 99,001 at the start of the 33-day period and 99,625 at end, which suggests we used 624 kWh which is right in our range including substantial AC use. Update: so we produced 624 kWh plus for 276 kWh surplus for total solar output of 900 kWh, which squares with what Solar City’s energy portal is reporting to me via the Internet.

And we used 168 kWh from National Grid, the cost of which was covered by what we sent back to the grid. Update: I posted the wrong month. Obviously from what I am saying, we used 0 kWh in the most recent period. The 168 kWh is from the previous period during which the solar panels were switched on halfway through.

I plan to call NG to make sure I understand everything on my bill, but there’s little ambiguous about “AMOUNT DUE $0.00.” Update: I did.

In any event, I am happy with the system so far. Update: Yep, I am happy.

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