Originally posted by CharlieEscCA
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Once the NBC business gets sorted out, either here, elsewhere, or by some workshop, and without denigrating its importance, NBC seems a somewhat minor matter in $$ terms at this point in time.
I'm somewhat more impressed with the idea that true T.O.U. tariff schedules, because the rates of such schedules are not a function of how much electricity is used but rather when it is used, thus separating the value of the power a system on NEM generates to offset a bill from the consumption that produces that bill. That means (NBC aside for a moment) that for design purposes a model's (PVWatts) estimate of hourly output coupled to an hourly rate schedule can be used to calculate how much revenue a system will produce that can be used to offset a bill for use, regardless of what that use may be - provided the generation is <100 % of use.
Doing so will also allow some interesting information. A couple that might be interesting or perhaps useful might be calculating the average revenue value per kWh of electricity generated by a system. Another is to be able to see the value of the electricity generated at various orientations, say per STC kW, and so compare whether or not for example, a 225 deg. azimuth, 20 deg. tilt will produce more revenue offset than a 270 deg. azimuth, 20 deg. tilt in inland San Diego using the new DR-SES times and proposed rates. (It will, BTW, by ~ $403-$375 ~ = $28/yr. less for the 270 deg. azimuth per STC kW using new DR-SES times and proposed rates, PVWatts and Miramar TMY3 data).
Once the value of generated power is separated from use, it opens up lots of possibilities. One example: If a 5 kW, south facing 20 deg. tilt system will produce $402 X 5.0 = 2010/yr. in revenue to offset a bill, it will do so regardless of how much, or when during a year that bill is accumulated, provided the system generates less than 100% of use. So, if a 5 kW system nets out at a cost of, say $17.5 K*.7 = $12,250, and generates $2,010/yr. worth of bill offset revenue, pretty much regardless of how much that bill may be (provided it's < $2.020/yr.), that may be useful information. NBC, such as it may be, can then be added to the bill, but the revenue to offset a bill will stay the same for the same system and model used to estimate system generation.
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