Simple AC-coupled solar production monitor /meter to control dump load / relay

Moving the goal post on folks is kind of a dirty move but the way your power agreements and utility billing works I can kind of see why it is necessary for the well being of your grid. I mean I'm in Texas so I shouldn't really say much about the well being of a grid but here we get charged separately per kWh for delivery (which pays for the grid infrastructure) and then we get charged for every kWh of electricity for the actual power.

I personally think net metering was a good idea to get people going but it is not sustainable long term going forward. Once you hit critical mass and everyone is producing solar during the day but everyone wants to use power at night, the system breaks down. Having said that, Australia works just fine on solar and wind: https://reglobal.co/a-grid-dominated-by-wind-and-solar-is-possible-a-case-study-of-south-australia/

I think in home self consumption will be the true name of the game. I don't mind paying the $5 monthly fee to have grid access and pay for the electricity I use from the grid including the delivery charge but $8/month/kWh sounds unsustainable. At $0.20/kWh that would require you to export 40 kWh/kW/month just to break even. That's 1.3 kWh/day for every kW of PV. in Texas at my location I can estimate to be producing about 3.4 kWh per kW of PV per day on average. That is a 38% tax on PV production at that point and makes it non-viable.

Home consumption will alter the snake oil salesmen's tactics as they will not be able to sell people on the idea that everything they produce will automatically offset their consumption. With no net metering, the bets are off and you have to do the math for yourself.

I don't even have my PTO in place but with my inverter I can just limit my PV to home consumption only and that is not something they can stop me from doing. I think this will be the future of solar production. My system is set up to be 94% self consumed with my usage/PV size and battery whether I have free nights or not. With free nights my math changes so I only self consume 66% and export 34% because I have no need for the daytime electricity if you give me free power at night. My contract with my REP (retail electricity provider) is for 24 months, after that they can re-evaluate and offer something different or I am free to choose a competitor if I want to.

As for EVs, I have one with a 93 kWh battery but I only charge about 12 kWh/day with the mileage I drive. I would not want to use my expensive EV as a home battery anyway, Lifepo cells for the house are still way cheaper than full battery replacements in EVs. Sure, for emergencies it'd be nice to have an additional 93 kWh storage that I could dip into but for normal use I'd never want to cycle that battery for my home power needs.

GregTR said:

Moving the goal post on folks is kind of a dirty move but the way your power agreements and utility billing works I can kind of see why it is necessary for the well being of your grid. I mean I'm in Texas so I shouldn't really say much about the well being of a grid but here we get charged separately per kWh for delivery (which pays for the grid infrastructure) and then we get charged for every kWh of electricity for the actual power.

I personally think net metering was a good idea to get people going but it is not sustainable long term going forward. Once you hit critical mass and everyone is producing solar during the day but everyone wants to use power at night, the system breaks down. Having said that, Australia works just fine on solar and wind: https://reglobal.co/a-grid-dominated-by-wind-and-solar-is-possible-a-case-study-of-south-australia/

I think in home self consumption will be the true name of the game. I don't mind paying the $5 monthly fee to have grid access and pay for the electricity I use from the grid including the delivery charge but $8/month/kWh sounds unsustainable. At $0.20/kWh that would require you to export 40 kWh/kW/month just to break even. That's 1.3 kWh/day for every kW of PV. in Texas at my location I can estimate to be producing about 3.4 kWh per kW of PV per day on average. That is a 38% tax on PV production at that point and makes it non-viable.

Home consumption will alter the snake oil salesmen's tactics as they will not be able to sell people on the idea that everything they produce will automatically offset their consumption. With no net metering, the bets are off and you have to do the math for yourself.

I don't even have my PTO in place but with my inverter I can just limit my PV to home consumption only and that is not something they can stop me from doing. I think this will be the future of solar production. My system is set up to be 94% self consumed with my usage/PV size and battery whether I have free nights or not. With free nights my math changes so I only self consume 66% and export 34% because I have no need for the daytime electricity if you give me free power at night. My contract with my REP (retail electricity provider) is for 24 months, after that they can re-evaluate and offer something different or I am free to choose a competitor if I want to.

As for EVs, I have one with a 93 kWh battery but I only charge about 12 kWh/day with the mileage I drive. I would not want to use my expensive EV as a home battery anyway, Lifepo cells for the house are still way cheaper than full battery replacements in EVs. Sure, for emergencies it'd be nice to have an additional 93 kWh storage that I could dip into but for normal use I'd never want to cycle that battery for my home power needs.

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I don’t have any problem with them changing the rules and economics for new customers. It’s those of us who spect $thousands or tens of thousands to ‘lock in our electricity costs for the next 20 years that has me pissed.

I’ll be OK because I installed my own system and was very frugal with system costs, so I’ve already pretty much broken even.

By my neighbor borrowed $25,000 from the city to install his system. He’s paying that loan off as an addition to his property taxes over the next 20 years. Those folks are getting screwed (or rather they are getting forced to invest more in a battery and a hybrid inverter).

They call it the ‘carrot tax’. - imagine if you grew carrots in your backyard but the city came and told you you had to pay a tax for each carrot you grew equal to what it would have cost you in the store.

Again, if they want to stop future installs of rooftop solar, I have no problem with that - it’s the tax being forced on us legacy customers after 15 years instead of 20 that has me worked up.

As far as killing new solar installs, it gets even better. They are going to move from Net Energy Metering which means you true-up every year, up Net Billing which means you true you monthly.

So no more building up credit during the summer to offset consumption charges in the winter.

Excess monthly production will be credited at wholesale, meaning $0.05/ kWh currently.

So in the summer when I’m generating 150% of consumption, that credit will now offset only 1/5th to 1/6th of my wintertime consumption.

Or even better, those Sumer months my overgeberation credit will amount yo something like $11.50 and for the full year, my total generation credit will or total to more that $75 or so.

So the best case is I’ll get $11.50 in credit to reduce the $32 on per kW taxes they are going to charge me and for the year, The $384 in solar taxes they will charge me will be offset by 20% for all the excess electricity I sent their way.

It’s going to force all the legacy customers to move to zero export. Which again, I don’t have a problem with nearly as much as the reduction of the 20-year grandfathering period to 15.

I already have a 10kWh house battery, so the storage I’ll need from an EV to get me through to the next day will be less than that used to drive 10 miles. I’m not worried about that wear and I’d much rather put that $10K or $20K towards an EV than a bigger and high-voltage house battery.

But absolutely, at least here in California, the only residential solar that’s going make sense will be 100% capture and self-use (True Zero Export).

Since I'm in Texas where the zero export is the only scenario that makes sense already I have fairly little remorse for you guys on the west coast .

My family in Europe has 20 year Net Metering in place and they do exactly what you guys could do; export in the summer during the day, use it in the winter at night. As long as the summer excess put little dent into the cost of electricity at the wholesale level this was fine. But with solar starting to hit critical mass I can see how not all electricity is created equal. TOU is there for a reason and it would be unreasonable to give someone watt for watt when they don't represent the same value.

The newly proposed PV "tax" (connection fee) is essentially a form of wealth tax. If you want to balance things out and bring up the bottom end it might make sense on paper. The problem is, like you said, not everyone who opted for solar bought it cash and is "wealthy". Some are paying it back under the idea that it made long term financial sense. Sounds like the solution is doing hefty system upgrades to be completely self-using. Again, I would never have purchased a system that relied on externalities like net metering being in place for 20 year durations, but that's just me.

I guess your argument on the EV makes sense if you're fine with only using the battery when the car is at home. The cost saving of not buying the home battery can be put into the vehicle sounds reasonable.

My batteries are coming tomorrow, I'm pretty excited about my system now!

GregTR said:

Since I'm in Texas where the zero export is the only scenario that makes sense already I have fairly little remorse for you guys on the west coast .

My family in Europe has 20 year Net Metering in place and they do exactly what you guys could do; export in the summer during the day, use it in the winter at night. As long as the summer excess put little dent into the cost of electricity at the wholesale level this was fine. But with solar starting to hit critical mass I can see how not all electricity is created equal. TOU is there for a reason and it would be unreasonable to give someone watt for watt when they don't represent the same value.

The newly proposed PV "tax" (connection fee) is essentially a form of wealth tax. If you want to balance things out and bring up the bottom end it might make sense on paper. The problem is, like you said, not everyone who opted for solar bought it cash and is "wealthy". Some are paying it back under the idea that it made long term financial sense. Sounds like the solution is doing hefty system upgrades to be completely self-using. Again, I would never have purchased a system that relied on externalities like net metering being in place for 20 year durations, but that's just me.

I guess your argument on the EV makes sense if you're fine with only using the battery when the car is at home. The cost saving of not buying the home battery can be put into the vehicle sounds reasonable.

My batteries are coming tomorrow, I'm pretty excited about my system now!

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Good luck with the new battery - what did you get?

The house battery I have now is sufficient to cover all but overnight loads of ~2.5kWh (fridges) and the ~3.5kWh morning surge before solar power gets strong enough to offset. So when the EV is out for a day, I’d only be looking at a maximum of ~6kWh imported from the grid.

They are forcing me to purchase $10/33kWh per month anyway, so as long as the EV is not out more than 5 days a month, occasional absence will be neutral to me.

I’m like you - I was suspicious the 20-year deal would change (or that the equipment would fail with defunct suppliers who could no longer back it up), so I put my system 4kW system in myself for $5000 rather than paying an installer $20-25,000.

Under the new rules being proposed, you can build a system which is sized at 150% of consumption (so that you can generate enough to offset consumption in winter months).

So I would be able to put in a 6kW system but it would need a house battery sized to capture most of overnight consumption.

That class system would cost at least $35K through an installer and I don’t think I could do it for much under $20K if I’m using all UL listed and city-approved equipment.

The extension of the 30% solar tax credits is nice and means net cost of ~$14K to $24K after credits.

Let’s be generous and say consumption cost was $2000, meaning 7 to 12 years to break even if everything works out.

But wait, there is that solar tax of $8/kW/month, or $576 in this case.

So now you are saving a maximum of $1424 per year versus what you’d be spending without solar, meaning that your beak-even will be 17 years if you paid an installer and 10 years if you do it yourself like me.

I’ve got friends with money who want solar primarily to ‘go green’ and the financial return is utterly unimportant to them. So the result of all of these changes will just be to reduce the market for solar installers to that group of rich individuals who want to ‘offset their carbon footprints’ no matter the cost.

Again, I’m OK with that for the new customers (though it’ll be devastating to the rooftop solar installer industry), but impacting the 1.4 million existing solar customers in California who’ve already drunk the coolaid rubs me the wrong way.

I’ll be OK in any case and I’m just trying to prepare myself for all options. It looks like it will eventually cost me $384 a year to continue to be authorized for export, so if I can find a solution (leveraging an EV I plan to buy anyway) to stop all export for under $2000 or at most $4000, I’d go back to being a regular ‘ol electricity customer (who just happens to consume very little from the grid).

33kWh per month translates to average consumption of 45W 24/7, do that’s my spec for a True Zero Export system - if I can never export at all and maintain a minimum import level of 20-40W always, I’ll just be paying for extra power when the weather is bad and when large loads such as my electric oven need more than my inverter capacity can deliver.

I'm getting a Homegrid Stack'd 33.6 kWh system. It can't be here soon enough. Today I had an hour power outage which is not common in my area but I guess the grid wanted to show me one last time who the boss is .

I stumbled into this interesting tidbit, which explains the reason you need 1.44kW before EV charging can commence:

The minimum charge current of the EV Charger is 6 A. According to the IEC 61851 standard, a lower value is not permitted.

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I guess I should consider myself lucky with my setup and Texas electricity pricing. I just learned about bitcoin miners and with the free nightly electricity they actually pose a net positive proposition with an ROI of about 16 months. I'm almost inclined to invest in a 3kW miner as it would be a net win for me even though it would probably be a net loss for the environment, something my son seems to be bothered by and got pretty salty when I suggested that we should buy one of these miners. 900 kWh of free electricity a month bothered him a good bit.

This article was just posted and seems quite apropos in our NEM discussion; https://pv-magazine-usa.com/2022/09/27/why-did-i-reform-my-views-on-net-energy-metering-nem/

GregTR said:

This article was just posted and seems quite apropos in our NEM discussion; https://pv-magazine-usa.com/2022/09/27/why-did-i-reform-my-views-on-net-energy-metering-nem/

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As soon as he said this:

‘I also believe that export compensation should be lowered from retail rates but not suddenly and certainly not retroactively.’

I knew he and I would be on the same page. It’s the changing terms on solar customers who have already made the investment in solar that has me most worked up.

The one thing missing in his argument is the higher cost of rooftop solar versus solar farm-scale solar. Solar farms have other social costs including unsightliness and rooftop solar has other benefits including jobs, so making a decision between the two is not one-dimensional but the difference in cost/efficiency needs to be considered.

My bottom line is that if a consumer has the resources to generate and consume their own solar energy without impacting the grid, they should be free to do that (and even encouraged / incentivized).

Charging a customer with solar who never exports to grad a solar tax or a higher electrical rates than a standard electrical customer should not be allowed.

A minimum monthly bill achieves that - if it gets too high, solid customers can go true off grid and rely on generators for backup instead of the grid. But at least a minimum monthly charge treats solar and non-solar customers equally.

I think the issue here is that there are two costs associated with the grid just like with anything else in economics: fixed cost and marginal cost.

Even if I only choose to supply you with 1kWh or electricity there is certain cost in maintaining the transformers, the meters, the line to your house, the billing department etc. This is what the monthly charge is meant to cover. Now charging more just because you have solar means that the billing is not true and not genuine and some of this fixed cost is rolled into the marginal cost of the utility which solar customers are not paying fairly.

The problem they're trying to solve is by rolling some of the fixed cost into the marginal cost is that you're essentially making a scenario where price discrimination exists; the richer you are and the more electricity you use, the more of the fixed cost burden you're straddled with. The problem is that this model falls apart with solar in the picture as you will have richer users who are now no longer paying "their fair share" compared to the poorer folks for the fixed cost aspect of the power delivery or the subsidy of the power delivery.

The solar fee is trying to "fix" this by putting some of the cost back on the solar folks. The problem is that it's a really tough pill to swallow but I think the situation reflects the truth or some shape of it.

Oh, today I got my battery installed, I had a great time with the installers, they did a really nice job with running conduit from the Sol-Ark to the Homegrid Stack'd system and using 4/0 wire between the two.

My Sol-Ark is fully closed loop communicating with the Homegrid Stack'd system and receives perfect and accurate SOC readings via CAN-BUS and I can still use Solar Assistant using Modbus on the same port with a splitter. The entire system "just works".

There is no doubt in my mind that this setup is the one to get if one can afford it. The Sol-Ark 15K is an amazing piece of equipment and the Homegrid Stack'd is a really nice package! I decided to max mine out so next week they will bring another module so I'll have 38.4 kWh in one nice stack that will just work amazingly well.

The units arrived with 50% SOC and I burned them down to 25% SOC and now, since it'sjust after 9PM I'm charging them from the gird for free. I'm about to load 20+ kWh into these bad boys absolutely free!

My PTO also came through tonight so I am going to finally start selling to the grid during the day and reaping some of the limited benefits of grid sell, but more importantly I will finally have an opportunity to really exercise my system and see what it's capable of!

GregTR said:

I think the issue here is that there are two costs associated with the grid just like with anything else in economics: fixed cost and marginal cost.

Even if I only choose to supply you with 1kWh or electricity there is certain cost in maintaining the transformers, the meters, the line to your house, the billing department etc. This is what the monthly charge is meant to cover. Now charging more just because you have solar means that the billing is not true and not genuine and some of this fixed cost is rolled into the marginal cost of the utility which solar customers are not paying fairly.

The problem they're trying to solve is by rolling some of the fixed cost into the marginal cost is that you're essentially making a scenario where price discrimination exists; the richer you are and the more electricity you use, the more of the fixed cost burden you're straddled with. The problem is that this model falls apart with solar in the picture as you will have richer users who are now no longer paying "their fair share" compared to the poorer folks for the fixed cost aspect of the power delivery or the subsidy of the power delivery.

The solar fee is trying to "fix" this by putting some of the cost back on the solar folks. The problem is that it's a really tough pill to swallow but I think the situation reflects the truth or some shape of it.

Oh, today I got my battery installed, I had a great time with the installers, they did a really nice job with running conduit from the Sol-Ark to the Homegrid Stack'd system and using 4/0 wire between the two.

My Sol-Ark is fully closed loop communicating with the Homegrid Stack'd system and receives perfect and accurate SOC readings via CAN-BUS and I can still use Solar Assistant using Modbus on the same port with a splitter. The entire system "just works".

There is no doubt in my mind that this setup is the one to get if one can afford it. The Sol-Ark 15K is an amazing piece of equipment and the Homegrid Stack'd is a really nice package! I decided to max mine out so next week they will bring another module so I'll have 38.4 kWh in one nice stack that will just work amazingly well.

The units arrived with 50% SOC and I burned them down to 25% SOC and now, since it'sjust after 9PM I'm charging them from the gird for free. I'm about to load 20+ kWh into these bad boys absolutely free!

My PTO also came through tonight so I am going to finally start selling to the grid during the day and reaping some of the limited benefits of grid sell, but more importantly I will finally have an opportunity to really exercise my system and see what it's capable of!

Click to expand...

Sounds like a really nice rig!

What did you pay per kWh for your batteries?

The Solark represents the Mercedes Benz of current Hybtids, from my perspective.

I’d love to put in a Solark-based rig but it just wouldn’t make economic sense for me.

My 2016-era electrical bill was $700/year, so spending $5000 on a 4kW Microinverter-based grid-tied array made sense and with tax credits, I’ve probably broken even by now (6 years later).

But I’m only going to be facing new charges when they force the solar tax on me, currently planned for 9 years from now.

Until then, the worst thing I might need to deal with is monthly billing (which means adding more solar panels to cover more of daily consumption; a better hybrid really won’t be much help.

At wholesale rates of $0.05/kWh, it’s hard to justify extra solar panels, but once you start talking $0.20-0.30 per kWh, even only over the winter months, it starts making sense very quickly…

Beyond more panels, I’ll eventually need more battery capacity if they ever change the rates to the point that a kWh exported during the month won’t cover the cost of a kW consumed late at night, but that’s where I’m hoping the EV will come in.

And with Emporias bidirectional charger + Energy Monitor priced at under $1600, that seems like a much more realistic budget to spend on overnight offset than the price of a Solark.

Backup power is absolutely not a priority for me - it’s just about generating enough electrical power to offset electricity biils (as long as that makes economic sense).

On the question of NEM agreements, I’m totally with you as far as new customers. The customers who have already hooked-up should not have the terms changed on them after the fact (bait and switch).

And if only wealthier customers can afford to take themselves completely off of the grid, they should have the freedom to do that. It results in more grid capacity and a healthier grid for everyone else.

And I’m even OK with a huge rehookup fee if you try to go off-grid and decide it was a mistake.

Aside from not changing the rules after the fact, my main thing is to apply the same rules to everyone. Call the solar tax an ‘export right fee’ or an ‘export fine’ on months your are caught exporting, and I’m 100% on board.

You grew carrots (generated energy) and ate them (consumed it) so you will pay us a tax on the market value of your carrots (an solar tax even if you exported no energy the the grid and are disconnected from it), I am not.

Yeah, I do realize that the Sol-Ark 15K is probably the top dog on the market today, but when you look at large scale residential PV, it actually starts making sense, even from a cost perspective.

All in, after the 30% federal tax credit I'll end up paying $2.56/W for my system, including the 38.4 kWh battery backup. That is a really competitive price. If I take out the cost of the battery I'm paying a mere $1.61/W after the federal credit.

Solar only cost:
$2.30/W cash, $1.61/W after federal credit. This is incredibly competitive in today's market. I got a Sol-Ark 15K, Tigo Optimizers, Aptos 440W panels, Unirack racking and mount system, grid disconnect switch and all conduit and wiring.

Battery cost:
$685/kWh cash, $480/kWh after federal credit. This is not as cheap as I could have gotten had I gone with Lifepower from signature solar which is now UL listed and would have worked fine, but this did include a day's work of two guys, conduit for the 4/0 wire, and about 30 ft of 4/0 wire.

With the solar, estimating a 20 year lifetime and 1.29 kWh/W/year I'm estimating 25.8 kWh/W generation which means about $0.105/kWh for electricity including the batteries and assuming 94% self consumption (these are the modeled numbers I got based on my usage data and optimal battery strategy). This hinges on no net metering, no grid export of any kind, just limit to load consumption and using the battery for solar storage.

Now if I can stay on my current power plan with free nights my math gets even better as I can easily assume that I will cover all my power needs and I can safely estimate about 35,000 kWh/year benefit from the panels. At that rate I'm looking at net cost of $0.044/kWh which is an absolute steal! This is again, no grid export and including the cost of batteries.

So yeah, $50k out of pocket for a system is definitely a lot of money up front and not for everyone. But if I assume that solar adds 3-4% to the value of a home I made a solid investment and I will get the money back almost immediately just by virtue of increased home value.

GregTR said:

Yeah, I do realize that the Sol-Ark 15K is probably the top dog on the market today, but when you look at large scale residential PV, it actually starts making sense, even from a cost perspective.

All in, after the 30% federal tax credit I'll end up paying $2.56/W for my system, including the 38.4 kWh battery backup. That is a really competitive price. If I take out the cost of the battery I'm paying a mere $1.61/W after the federal credit.

Solar only cost:
$2.30/W cash, $1.61/W after federal credit. This is incredibly competitive in today's market. I got a Sol-Ark 15K, Tigo Optimizers, Aptos 440W panels, Unirack racking and mount system, grid disconnect switch and all conduit and wiring.

Battery cost:
$685/kWh cash, $480/kWh after federal credit. This is not as cheap as I could have gotten had I gone with Lifepower from signature solar which is now UL listed and would have worked fine, but this did include a day's work of two guys, conduit for the 4/0 wire, and about 30 ft of 4/0 wire.

With the solar, estimating a 20 year lifetime and 1.29 kWh/W/year I'm estimating 25.8 kWh/W generation which means about $0.105/kWh for electricity including the batteries and assuming 94% self consumption (these are the modeled numbers I got based on my usage data and optimal battery strategy). This hinges on no net metering, no grid export of any kind, just limit to load consumption and using the battery for solar storage.

Now if I can stay on my current power plan with free nights my math gets even better as I can easily assume that I will cover all my power needs and I can safely estimate about 35,000 kWh/year benefit from the panels. At that rate I'm looking at net cost of $0.044/kWh which is an absolute steal! This is again, no grid export and including the cost of batteries.

So yeah, $50k out of pocket for a system is definitely a lot of money up front and not for everyone. But if I assume that solar adds 3-4% to the value of a home I made a solid investment and I will get the money back almost immediately just by virtue of increased home value.

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$0.105 per kWh or $0.044 per kWh are both excellent electricity rates by California standards. We may $0.30/kWh off peak and $0.50/kWh over summer months (and $0.20/0.25 over the winter).

But install is a big part of the cost and scales better with larger systems. I’m guessing you consume a great deal more than the ~4.5MWh/year that I consume.

My system was circa 2016 and because I installed it myself, the entire 4kW grid-tied system with panels and Microinverters cost me $1.25/kW ($5000) or under $1/kW with tax breaks at that time.

Now that I’ve basically paid for that array, hopefully I’ll be able to find ways to adapt to the changing rules without it costing me an arm and a leg.

Your battery a $685/kWh was a bit pricey, but including install probably worth it.

When I wanted a battery 18 months ago, there were no affordable OTS options.

I built my $14.5kWh battery for only $104/kWh based on rated capacity but I suspect actual capacity falls short of that. Currently, the most I’m using in the peak of summer is 8kWh so it cycles at least 55% of it’s rated capacity with ease.

Hopefully my future EV will give me total storage capacity 2-3 times what you’ve got at an overall cost/kWh that is not much higher per kWh…

And hopefully by that time there will be a bidirectional-charger-based hybrid solution that allows to store all of my daily generation for overnight consumption offset for a fraction of what a Solark costs…

Yeah, I used 4.2MWh in July alone so my consumption is a "bit" more than yours.

My pre-solar-purchase electricity rate was $0.089/kWh all day every day. This is what made solar ROI not really viable in Texas in the past and the only people who bought it were the ones who wanted to virtue signal or got duped by sales people. Historically, solar has been getting cheaper year over year which made the proposition of buying now vs. later even less appealing.

The cheapest rates currently available are $0.13 for a 36 month lock-in period so even at that rate solar makes sense. Combine that with the inflation and price uncertainty of solar and I think the time was now to jump in.

The non-tangible benefit for me is the addition of resiliency. I WFH now so having reliable power is a bit more important now than it ever was.

GregTR said:

Yeah, I used 4.2MWh in July alone so my consumption is a "bit" more than yours.

My pre-solar-purchase electricity rate was $0.089/kWh all day every day. This is what made solar ROI not really viable in Texas in the past and the only people who bought it were the ones who wanted to virtue signal or got duped by sales people. Historically, solar has been getting cheaper year over year which made the proposition of buying now vs. later even less appealing.

The cheapest rates currently available are $0.13 for a 36 month lock-in period so even at that rate solar makes sense. Combine that with the inflation and price uncertainty of solar and I think the time was now to jump in.

The non-tangible benefit for me is the addition of resiliency. I WFH now so having reliable power is a bit more important now than it ever was.

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With consumption like that, your rig would practically qualify as a small Solar Farm here on n the Bay Area!

Between the lowest in the land electricity rates in Texas slowly creeping up, the severe grid issue of a few years ago, and the continued trend towards lower and lower cost for solar technology, it finally makes economic sense to add solar in Texas - that’s a major milestone!

I would love to have a high-end system like yours but with my much more modest consumption levels, it just wouldn’t make economic sense (tax breaks or no).

And at your consumption levels, I agree - use of an EV as extended battery wouldn’t make sense - that’s slot of power you’d wast anytime the EV wasn’t present and you’d be cycling the EV close to 200 miles equivalent per day.

For me, the ‘gap’ I’ve got to close between my existing 8-10kWh battery and offsetting load all way through until after the breakfast surge when solar reaches the level to once again take over translates to only 10-20 miles of driving daily (and if the EV is not there to capture a days excess production, it’s not that big of a deal in terms of lost energy).

So the architecture I see eventually becoming commonplace here in California probably won’t make sense in high-consumption areas like Texas…

Maybe an old thread, but good discussion. How did those CT clamp power switches work out? Could be useful for some cases.

You mentioned Emporia, hoping to get them to offer a configurable excess solar or power measurement switch, not so likely I think... If you have any home automation inclination, there is a python library, PyEmVue which allows one to read the data from Emporia Vue, and control Emporia EVSE. It still works through Emporia's cloud, but, it works. There is integration with Home Assistant for it also. Further down the hacking line is ESPhome which can replace the firmware on the Emporia Vue, so you can read the power data locally without using the cloud at all.

I have Home Assistant and I am using the Emporia integration with it. Since I currently have free nights and also a battery, I have yet to invest too much time into getting things automated to maximize solar use, I'm better off just exporting all the excess and charge my EV at night.

But if the time comes where free nights go away I'll be sure to look more into it.