Efficiency vs $ is always an interesting exercise. Many variables. I was looking to replace my mini splits last year and ran the numbers on SEER ratings vs projected life kWh usage, it was a wash. The lower price of the lower SEER units plus the expected cost of power equaled the higher initial cost, lower consumption high SEER units. Weird, it’s almost like the manufacturers worked that out before setting their retail prices.
Also, when I was shopping for a water heater I found the best option was to buy cheapest electric one available and adding a couple extra solar panels to the array.
Recently my power company started charging a monthly fee for each kW of rated power for my solar panels so my 9 year history of ‘just add panels’ no longer works. Essentially they reduced the cost savings of solar by 50% with their new fee. It adds a level of complexity to my $/efficiency calculations.
Where the heck do you live? The set of Running Man or Hunger Games?!
California?
Ha! Right? I live in a very rural section of South Carolina where our power is provided by an electric cooperative called Pee Dee Electric. Last June everyone with grid tied solar got a letter saying we had 3 options… 1) pay $X per kw of labeled solar to continue with net metering. Or, 2) disconnect our panels from their grid, buy all our power from them and pay the usual monthly meter fee. Or 3) don’t pay their fee of $X per kw of labeled power, leave our panels connected to their grid and any energy that gets fed onto the grid will belong to the power company where they’ll sell it back to us and our neighbors at full retail price receiving no credits or payments for the energy we generate.
The power company missed a 4th option that us PV owners have… buy a battery bank to store our power and tell Pee Dee Electric Cooperative to pound sand. Which is why I’m here, to learn about the equipment I’ll need to disconnect from their grid.
$0.12/kwh is pretty steep for around here. Last time I checked some folks were paying as little as $0.07 to $0.09 for residential service. $0.12 was high enough to make PV worthwhile where if I was paying $0.07 to $0.09 I probably wouldn’t have bothered.
My beef is that before I installed solar, my power bills were averaging around $55/month, more in the winter, less in the spring and fall but averaged out over the year $55 was about right. I used that year to calculate how much PV to install. In SC it’s against the law to sell our excess electricity so I sized the array pretty close so I wouldn’t be wasting any unused kWhs. It was great for the first year, most months were $0.00. Then they started charging a Meter Fee. First it was $12/mo , then $13, then $14 , then $17/mo and now with their current pricing scheme, I’m paying $45/month for every month that I don’t need to buy any grid power. Sure, for that fee they’ll continue to act as a 12 month battery bank begining June 1st each year, same as they did for the 8 years before their Pay-Per-PV-kW fee.
Summers are pretty warm here so I start off the year basically using all the power I generate but come fall I start banking the unused kWh. Then usually in January and February I use up those banked credits, sometimes needing to buy a few extra grid kWhs to get though late February. And by mid March I’m back to generating more than I use with the excess being credited to my account. Well, credited until midnight May 31 when all credits default back to zero and the new 12 month battery (net metering) year begins again.
Anyway, without solar my monthly bill was $55 and with this new Pay-Per-PV-kW fee my bill is $45.
So basically I bought and installed 5,000 watts of PV to save ten bucks a month on my light bill. Not exactly the ROI I was looking for.
How much would the bill cost you right now if no panels and no net metering?
$45 - $17 = $28, is that the monthly fee for 5kW of PV?
Almost a bargain compared to the California NEM 3.0 proposal. PG&E asked for $12/kW/month ($60 in your case), PUC approved a plan at $8/kW/month ($40), but Newsom announced it needed work, and we don't know what will be implemented.
Is your fee based on STC rating of panels, or on inverter rating, or peak backfeed to grid?
Various games, including multiple panel orientations to reduce peak, extend hours. Export limit to not cross the agreed threshold.
Do they still credit $0.12/month if you pay their photon tax?
California was going to credit us 25% (of $0.20 rate, so $0.05 credit.) Which happened to be exactly the photon tax; zero net credit.
Even if it feels like you're being screwed, their deal may be OK if your production/consumption hours are such that you export 100% then later import. Your 5kW should produce 25kWh/day 750kWh/month so photon tax is $0.037/kWh
Server rack batteries look to me like they will cost $0.05/kWh if they last the claimed 6000 cycles (and they may not.)
So if 100% or even 50% of your power cycles through net metering, the photon tax is competitive.
If only 25% of your power is banked and 75% is consumed when produced, then you may be better off with option 3 (and you have the option of zero-export just to spite them.) Turn on loads to consume surplus when possible.