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I don't know, do I need to use emoticons to communicate in this thread? Others have pointed some of this out, but let's recap:
1) If the system is sized for 100% offset, the expected NET consumption at the end of the year is approximately 0. By the estimates shared earlier in the thread, 100% offset *will* be achieved, since kWh credits generated during this time of year through spring will be consumed in the summer by A/C and other cooling loads. If that is true, then the rate plan truly doesn't matter, there are no "savings" left to be had.
2) For TOU to make sense, the PV system needs to be small enough that it is unable to produce enough kWh to cover the full year's consumption. If this is true, there is at least the possibility that a TOU $ credit could come out ahead of a straight kWh offset.
3) Any TOU plan with 2-8 pm peak period is unlikely to be net negative during the peak period, if A/C represents a big portion of the load. That rules out the -A and -B plans. The -D plan is still 12-6 pm, so there is a chance that it will come out ahead. The on-peak credit for wintertime generation is 0.22 / KWh. The credit will get consumed at at 0.34 / kWh in the summer. Therefore, 100 kWh of peak generation in winter is only worth 65 hours of peak consumption in summer. If the customer is not net negative in peak periods during summer, that credit gets eaten up fast, before off-peak loads get covered.
In other words, the window in which TOU makes sense is narrow... in general terms, the system needs to be big enough that consumption is net negative during summer peak, but small enough that consumption is net positive for the year. I don't think enough information has been shared to know for sure whether this sytem would benefit under that plan or not. I would be skeptical that the SCE customer service agent on the phone is running the generation estimates and consumption calculations tightly enough to make a thoughtful recommendation either way.
1) If the system is sized for 100% offset, the expected NET consumption at the end of the year is approximately 0. By the estimates shared earlier in the thread, 100% offset *will* be achieved, since kWh credits generated during this time of year through spring will be consumed in the summer by A/C and other cooling loads. If that is true, then the rate plan truly doesn't matter, there are no "savings" left to be had.
2) For TOU to make sense, the PV system needs to be small enough that it is unable to produce enough kWh to cover the full year's consumption. If this is true, there is at least the possibility that a TOU $ credit could come out ahead of a straight kWh offset.
3) Any TOU plan with 2-8 pm peak period is unlikely to be net negative during the peak period, if A/C represents a big portion of the load. That rules out the -A and -B plans. The -D plan is still 12-6 pm, so there is a chance that it will come out ahead. The on-peak credit for wintertime generation is 0.22 / KWh. The credit will get consumed at at 0.34 / kWh in the summer. Therefore, 100 kWh of peak generation in winter is only worth 65 hours of peak consumption in summer. If the customer is not net negative in peak periods during summer, that credit gets eaten up fast, before off-peak loads get covered.
In other words, the window in which TOU makes sense is narrow... in general terms, the system needs to be big enough that consumption is net negative during summer peak, but small enough that consumption is net positive for the year. I don't think enough information has been shared to know for sure whether this sytem would benefit under that plan or not. I would be skeptical that the SCE customer service agent on the phone is running the generation estimates and consumption calculations tightly enough to make a thoughtful recommendation either way.
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