Redhill_qik
Active Member
This is a really bad chart and I think it is this way to mislead. The costs are average annual cost for that hour, but the TOU rates are based on both Standard and Daylight Saving time. The demand/cost shifts because humans fall the local clock time and not a fixed UTC schedule.
This graph is from CPUC "White Paper" which proposes NEM 3 as a solution to a problem with NEM1,2. That problem, as described in the paper centers on the above graph: solar customers need peak period power, just like everyone else, but because they get credit for their exported solar, they pay less than everyone else. NEM3 advocates describe this as a subsidy of (rich) solar owners paid for by (poor) non-solar customers.
Back to the title of this entire thread, NEM 3 and energy products. It seems to me that the solution is widely distributed short term storage to level the demand. This will reduce peak generation load to the average, which is a fraction of the peak. By locating storage near to consumers, peak transmission loads are reduced as well.
Today, with or without solar, a customer with a battery can completely avoid using power during peak periods, thus saving the utility substantial money, according to the graph. This savings gets passed on to all customers.
I have a single Powerwall charged from my solar. I use essentially no grid power, all year long, during peak periods.
The NEM3 proposal starts with radically increasing cost for all solar customers, and then discounting that a bit for battery storage. That seems backwards to me, because battery completely eliminates the problem, solar or not.
What am I missing?
I extracted the actual costs from the five worst hours to compare to the E-TOU-C rate
Time | Cost $/MW |
---|---|
17:00-18:00 ST | $259.3 |
18:00-19:00 ST | $316.9 |
19:00-20:00 ST | $230.5 |
20:00-21:00 ST | $161.0 |
21:00-22:00 ST | $96.6 |
So the average is $212.9/MWh or $0.2129/kWh. In comparison the E-TOU-C generation Peak rate for summer is $0.2006/kWh which is very close. The rest of the day is mostly under $50/MWh or $0.0500/kWh and the E-TOU-C Off-Peak generation rate for summer is $0.14722/kWh. Maybe there is a slight loss during Peak, but there is a big gain for the rest of the day. Winter generation is $0.15189/kWh for Peak and $0.13687/kWH for Off-Peak, so again a big win for the Off-Peak generation cost recoupment.
Even without a battery solar will be either still be exporting to the grid during early Peak or lowering the demand in the costly late summer months and at night everyone is paying more than it costs.