What to do with no net-metering?

[SunnyinIA]

Hey everyone, first post here, been lurking trying to learn for awhile. The past few months I have been doing a bunch of research, and learning as much as I can, before going solar. A little info to give you all an idea of my specifics... My wife and I built our house in 2020, so fairly new, and we are in central Iowa. We don't use a ton of electricity, a total of 6,163 KWH for the past 12 months. We are both pretty frugal people, and started looking at solar as an investment to wipe out our electricity bill. Number crunching put our need at a 4.8kw system to cover 100% of our yearly usage, but was planning to go a bit bigger to cover future needs with growing kids. With the research I saw that Iowa is a net-metering state, and just went forward on that assumption. My plan is to build a ground mount array for several reasons- 1- I don't want to drill holes in my new roof that could eventually leak 2-Easier cleaning of snow and dirt(live on gravel road) 3- Easier maintenance if needed 4- Better cooling for efficiency 5- Plenty of land with no shade. Our house has propane for heat, water heating, and range cooktop, and electric for everything else.

So with all that out of the way, on to the question/issue. After all my time and research, I just now thought about checking in to our utility company, to find out that they do not net-meter. I guess the Iowa law is just to recommend that providers net-meter, but it is not a requirement. I snipped the exact wording from their website and attached it. Basically, they don't bank anything, and buy back the energy at avoided cost only. This has put me back to step one, questioning if it even makes sense to go with solar. Our electricity currently costs roughly $0.12/kwh, and they buy it back at $0.025/kwh, so any energy we don't use as its created would lose almost 80% of its value going back in to the grid, just to pay full price to get it back. I am not even sure where to start on calculating a payback period and figuring out if solar makes sense for us. Is there some way to figure this out? I feel like the chance of us using the energy at the exact time its created is pretty low, so most of what we make would go back to the grid. We can change our habits by using more power at times when we are making it, like doing laundry during the day, running space heaters during the day in winter, using the oven when the sun is out, and all that, but that will only help a little bit. I have come up with some options, but I am not sure any are that great... 1- Use the go big or go home method and build an array 4-5x what we really need to still offset our bill by making a bunch.(expensive) 2- Get battery storage to store what we make instead of selling it cheap to the grid.(quite expensive) 3- Don't get solar. I could use some help talking off the ledge if anybody has a better solution, or a good way to calculate the dollars and cents of use/buyback/consumption. Sorry for the long post, and appreciate any help/advice anybody may have.

 

[robby]

At $.12/KWh electricity rate you are never going to get a reasonable length of time on ROI if ever!
You need to decide if you want it for energy security, Grid Independence etc.
If you want it for those reasons then I suggest an AIO inverter system with batteries.
Next you would have to decide how much money your willing to spend.
If it is Grid tied then I am pretty sure your going to need equipment that is approved by your State. This tends to be Teir1 equipment and it's not cheap like the non approved equipment on the market.

Personally if I was you and the power was reliable I would spend the money on appliances and other home improvements that can reduce your electricity bill.
Mini Split Heat Pumps and Hybrid Hot Water heater will cut a lot of your existing bill and should energy prices rise this is the kind of equipment you would want in the house if you do decide to go Solar in the future.

 

[Hedges]

The fine print says if you interconnect PV, you lose the "heat rate".
That appears to say your electric rates change, which would be a killer.

Otherwise, although they don't do net metering, they allow backfeed and pay $0.025/kWh.
I figure if you buy GT PV hardware for $1/W and install it with your own free labor, it produces power for $0.025/kWh over 20 years.
In other words, you break even for power you backfeed because not used, but save almost 80% of your $0.12/kWh rate for power you use when produced.
That wouldn't be a terrible deal. If you use most power at the time produced. If you install it yourself. But only if your rate doesn't change, which it apparently will.

So possibly a zero-export system. Same at GT PV except current transformers monitor grid connection so PV production curtailed to avoid export. Have to see what connection agreement is required for that, and if it also changes your rate schedule.

As Robby said, there may be better investments. Both in efficiency and in the financial markets.
Maybe a small battery/PV system with grid input would support communications and a bit more during power failures. Possibly installed on an RV for dual use?

 

[SunnyinIA]

Our reasoning for going solar is to erase as much of our electricity bill as possible, we don't like bills and owing anybody money. We are currently debt free, and just like to look at ways to chip in to bills we have. We also have money to invest, so if we can invest that money in to a solar array that would take away a bill and be an investment, its a win win. I guess I did forget to mention in my post, I fully intend to DIY it. I have the equipment and ability to do it all, and have an electrician in the family to help with that part. We are willing to spend a pretty decent amount of money, as long as it has a ROI in a decent amount of time. Unfortunately and fortunately, being a new house that we had built, we did go with high efficiency everything. We had the builder add extra insulation, high efficiency windows, all energy star appliances, and high efficiency HVAC pieces. I say unfortunately because it doesn't really allow for much improvement for the costs required, but that's why we chose what we did. In the end, it worked out pretty well, because we have a 4,000 sqft house running on 6,200kwh per year.

As far as the heat rate, that is a special rate program that our power company started this year. Its for anyone who adds high efficiency space heaters to their house, on a separate meter, they get a rate that's basically half of regular just on that meter, plus a $9 standard charge instead of their regualar $35. We do not have that, so that bullet point would not apply to us. Adding solar wouldn't change our rate any.

 

[robby]

If your not interested in ROI then the only question is how much money do you want to spend.
If you do not want to get bills from the power company your going to need an AIO unit and a fair amount of batteries.

 

[Bud Martin]

Our reasoning for going solar is to erase as much of our electricity bill as possible, we don't like bills and owing anybody money. We are currently debt free, and just like to look at ways to chip in to bills we have. We also have money to invest, so if we can invest that money in to a solar array that would take away a bill and be an investment, its a win win. I guess I did forget to mention in my post, I fully intend to DIY it. I have the equipment and ability to do it all, and have an electrician in the family to help with that part. We are willing to spend a pretty decent amount of money, as long as it has a ROI in a decent amount of time. Unfortunately and fortunately, being a new house that we had built, we did go with high efficiency everything. We had the builder add extra insulation, high efficiency windows, all energy star appliances, and high efficiency HVAC pieces. I say unfortunately because it doesn't really allow for much improvement for the costs required, but that's why we chose what we did. In the end, it worked out pretty well, because we have a 4,000 sqft house running on 6,200kwh per year.

As far as the heat rate, that is a special rate program that our power company started this year. Its for anyone who adds high efficiency space heaters to their house, on a separate meter, they get a rate that's basically half of regular just on that meter, plus a $9 standard charge instead of their regualar $35. We do not have that, so that bullet point would not apply to us. Adding solar wouldn't change our rate any.

View attachment 114114

'As far as the heat rate, that is a special rate program that our power company started this year. Its for anyone who adds high efficiency space heaters to their house, on a separate meter, they get a rate that's basically half of regular just on that meter, plus a $9 standard charge instead of their regualar $35. We do not have that, so that bullet point would not apply to us. Adding solar wouldn't change our rate any.'

So that will be $0.06/kWh, really cheap. I wonder how they will know if you are plugging in other devices beside the heaters in winter time. Do they offer that for high efficiency AC too?

 

[Hedges]

If your not interested in ROI then the only question is how much money do you want to spend.
If you do not want to get bills from the power company your going to need an AIO unit and a fair amount of batteries.

With grid tie backfeeding the grid, you'll get $0.025/kWh which is what the kWh cost you (amortized equipment cost over 20 years assuming DIY).
Power you use when produced, you avoid paying $0.12/kWh, saving $0.095/kWh
Power you consume from grid in excess of PV production (especially at night) you'll just pay the $0.12/kWh

You could put in batteries to save your $0.025/kWh self-generated power and avoid paying the $0.095 extra, but batteries will cost you at least $0.05/kWh. That's not including battery inverter, and is assuming the batteries really do last rated life.

So I could see putting in PV to offset about average daytime load, a bit more. Try to schedule loads to make use of it.
You can do something with batteries for convenient backup.

There are some inexpensive units, component and all-in-one
SolArk is a pricey all-in-one many people are happy with.
There is Schneider, SMA (which I have), several other brands.

A lot of people are using LiFePO4 "server rack" batteries now. Some brands reported behave better than others (probably BMS allows more surge)

Plan everything to fit together, including battery talking to inverter and PV series/parallel configuration meeting voltage and current limits of equipment before buying anything.

 

[robby]

With grid tie backfeeding the grid, you'll get $0.025/kWh which is what the kWh cost you (amortized equipment cost over 20 years assuming DIY).
Power you use when produced, you avoid paying $0.12/kWh, saving $0.095/kWh
Power you consume from grid in excess of PV production (especially at night) you'll just pay the $0.12/kWh

Yes but two problems with that. He says he "does not like Bills", so I assume he wants to be off the Grid or not pay anything other than a minor amount. The second problem is assuming that any inverter will last 20 Years. I will be happy if mine lasts 12 years.

You could put in batteries to save your $0.025/kWh self-generated power and avoid paying the $0.095 extra, but batteries will cost you at least $0.05/kWh. That's not including battery inverter, and is assuming the batteries really do last rated life.

And the chances of it lasting the rated life are going to be very dependent on the quality and price you pay for those batteries.

So I could see putting in PV to offset about average daytime load, a bit more. Try to schedule loads to make use of it.
You can do something with batteries for convenient backup.

I agree that is his best option but I am not sure he is interested in just cutting 35% off of his bill. Even if he does that the ROI is still very long.

There are some inexpensive units, component and all-in-one
SolArk is a pricey all-in-one many people are happy with.
There is Schneider, SMA (which I have), several other brands.

SMA Sunny boy would probably be a good match assuming he only wants to offset the daytime usage. I have seen a few of those Inverters that are 10 years old and still running perfectly, minus the half dead LCD screen.

A lot of people are using LiFePO4 "server rack" batteries now. Some brands reported behave better than others (probably BMS allows more surge)

Yep! A good Teir1 5KW pack using a BMS that is using a Relay can do 150A of surge. I don't trust most of the ones designed for Telecom use to go past 50A reliably.

Plan everything to fit together, including battery talking to inverter and PV series/parallel configuration meeting voltage and current limits of equipment before buying anything.

That is sound advice.

 

[Hedges]

Name brand grid tie inverter should last 20 years or more. Sunny Boy, optional warranty that long. Of course, it is only operating up to 12 hours per day. If it does get replaced once, your power costs $0.03/kWh
Battery inverter operating 24 hours per day? Sunny Island is warranted 10 years. If coupled with Sunny Boy, it has an easy life unless you draw heavily at night. At $1/W (msrp) it is a more expensive solution-*. (there are some new ones on eBay for half that)

Some people get a rack full of server-rack batteries. That brings the current needed for a house down to the range servers might have consumed.
I went for a minimal size battery (one night's worth) and AGM, due to my grid-backup application. Server rack batteries could be good fit for OP. I'd rather have communication between BMS and inverter, don't know which ones for server rack.

The reason I question cycle life is a study where only 5% made it to rated life. So I wouldn't bet on that $0.05/kWh battery, assume $0.20/kWh and anything longer is a gift.

 

[SunnyinIA]

Sorry, I have been slammed the past week. So reading through everything from you guys, I just did some simple math, and its not looking good. I am using basic numbers of our usage at 6,200kwh per year and needing a roughly 4.8kw system. Thinking over our usage, I am estimating that we use about 1/3 of our energy at the times a solar system would produce it, or 2,067kwh. That energy would be worth the full $0.12/kwh, while the other 4,133kwh would be worth the $0.025/kwh, bringing the years worth of energy production to $351.37. If I go off a $1/watt price of $4,800, that would make the payback period 13.7 years. I think we could/would change our energy usage patterns to use 50% or more of our energy during production times, which would mean we would get 3,100kwh at $0.12 and 3,100kwh at $.025, for a total of $449.50 per year. Even at that, it would be a payback of 10.7 years. That is also assuming the system would only cost $4,800, there would be no other cost increases(think insurance), and no maintenance costs for that whole period. That's not exactly a great return on a DIY system.

 

[foggysail]

I had an 11.2KW system installed and am waiting to get grid tied. My annual usage is just over 8,500kwh which would make one think I am in overkill.....maybe. My reasons to stick as much as my wife would allow onto the roof (she hates looking at them) is my neighbor's trees, NOT payback from the utility.

Sure, I expect some money from them IF the system significantly produces more than I use. My intention is to continue being a power consumption pig without monthly bills to pay for it AND I DO EXPECT TO SEE KWH COSTS SOAR. OK, sure there was my initial upfront cost but I can live with that.