OT: Solar panels on house

[af102]

I recommend watching a video one of the biggest tech reviewers did about the first year with his Tesla Solar Tile+Battery setup.

The TLDR- lives in NJ which has net metering. Spent ~$120k on the setup, got ~$28k in tax credits, so he paid a little over $90k for a 29 Kw array and 3 power wall batteries that can store 40.5 Kwh.

He used ~54Mwh of power in a year that cost ~$9600 if it all came from the grid (including an electric car, so charging at home), so the payback is between 9-10 years. He didn’t pay for any electricity from the grid for the whole year because of all the excess he sold back in the fall/spring.

Solar isn’t as good of a deal in GA because our net metering isn’t a 1 to 1 swap. If you sell excess power to the grid, GA Power pays you the wholesale price they would pay to other providers instead of just crediting you with the amount sent back. You are better off having a bigger battery system to store all the power you capture because the economics are more favorable never using power from the grid compared to selling excess.

 

[LordMcBuckethead]

I don't think it makes much sense in our part of the country (MS) because of the 25ish year payback by which time it's about time to replace the panels and wiring and you've already replaced the batteries, probably a couple times which I'm not sure they always include in your payback timeline, they stick those in maintenance category. They aren't used as much Nov-March either when it's cloudy cold and wet so it's hard for them to pay for themselves that time of year.
I'm all about solar for remote uses, it's not that I'm against solar at all. I've got a 180 watt panel on top of my pontoon that charges battery for all of my sound system, spot lights, little party lights, charging ports for phones, and with an inverter we can make frozen drinks with a blender. The starter battery on the boat has a solar trickle charger that stays on while it's sitting. I've got one small panel on my storage shed also to run some LED lights inside and security lights on outside. I've got solar yard lights all around the yard too.
There's a guy on YouTube named Will Prosser that can explain how to do anything with solar from a couple yard lights to an entire home if you want to try some of it yourself.

It makes a great deal of sense in MS. We get over 5 solar hours a day on average. That is 8-10 in the summer and 3 in the winter.

 

[The Peeper]

It makes a great deal of sense in MS.

Ahhh, so thats why we see sooooooooo many homes w/ solar. Got it.......

 

[LordMcBuckethead]

I remember looking at this when my åsshole neighbor put a bunch of solar on his roof 5 years ago when I lived in DFW. It was over 20 years to break even and said peckerwood was in his late 60's. I was happy to point out that he would have live in the house until he was 90 just to break even on his investment.

If you want to offset your energy costs going forward use the money you'd spend on solar to buy a broad portfolio of high yield bonds and dividend producing stocks. Apply that income to your power bill and sell the holdings when you go to the old fogey home. That's a much better investment unless you live in a location paying more than $.25 per kwh. That's when you start getting to a reasonable ROI on solar.

My payback time frame is 9.6 years for a 22kw system with battery storage.... what kind of math are you doing?

 

[LordMcBuckethead]

I recommend watching a video one of the biggest tech reviewers did about the first year with his Tesla Solar Tile+Battery setup.

The TLDR- lives in NJ which has net metering. Spent ~$120k on the setup, got ~$28k in tax credits, so he paid a little over $90k for a 29 Kw array and 3 power wall batteries that can store 40.5 Kwh.

He used ~54Mwh of power in a year that cost ~$9600 if it all came from the grid (including an electric car, so charging at home), so the payback is between 9-10 years. He didn’t pay for any electricity from the grid for the whole year because of all the excess he sold back in the fall/spring.

Solar isn’t as good of a deal in GA because our net metering isn’t a 1 to 1 swap. If you sell excess power to the grid, GA Power pays you the wholesale price they would pay to other providers instead of just crediting you with the amount sent back. You are better off having a bigger battery system to store all the power you capture because the economics are more favorable never using power from the grid compared to selling excess.

Once the batteries are full, which happens mid day if you limit your energy use while you are at work, you then sell back at the wholesale rate. If you sized our system correctly, you bill would be negative every year.

 

[LordMcBuckethead]

Ahhh, so thats why we see sooooooooo many homes w/ solar. Got it.......

You don't see that many houses with solar because our entire population in the state are poor, or have you forgotten.

 

[af102]

Once the batteries are full, which happens mid day if you limit your energy use while you are at work, you then sell back at the wholesale rate. If you sized our system correctly, you bill would be negative every year.

I work from home, so I’m drawing power all day. My gas bill for the car is essentially nothing these days with WFH and electric bikes, but my power bill is up for the extra hours of full AC.

I would go solar if my house didn’t have 6 40 foot trees all sitting on the south side of the yard. My whole roof is shaded most of the day which helps with cooling in the summer, but would definitely limit my solar output.

 

[LordMcBuckethead]

Ahhh, so thats why we see sooooooooo many homes w/ solar. Got it.......

The math is rather simple to figure out cost versus money saved. Mississippi gets a ton of solar energy for 9-10 months of the year in Starkville which is more than enough to offset your entire bill in the state. My system would cost 50k to replace my entire usage including the necessary batteries. 50k * .7 due to the tax credit you receive is $35k. I currently use 2259kwh per month with 4 County power with a bill around 300 per month. That puts my system at a 9.72 years payback, but over the life of the panels and battery cycle charge limits, it would save me $54,000 without even talking about increased cost of electricity over the next 25 years.

Now, if I just invested that money in the S+P over the next 25 years, my balance would be around $400k, assuming a double every 8 years. ±

So yes, the solar array will save you money over the 24 year life span, but investing the money would save you considerably more. But that is a different conversation.

 

[The Peeper]

"You don't see that many houses with solar because our entire population in the state are poor."

You have to be just a trolling crackhead. Our "ENTIRE population in the state is poor". Damn, you're ruining my retirement, I was about ready to 100% retire instead of 50% and now you tell me I'm poor? Going to have to sell my double wide to pay my power bill this month since I can't afford solar.

 

[PooPopsBaldHead]

My payback time frame is 7.6 years for a 22kw system with battery storage.... what kind of math are you doing?

When you calculate payback you should include the loss of potential gains from investing that extra money.

If you buy a $25,000 solar system it takes you 7.6 years to save $25,000 in electricity. If you invest $25,000 in the S&P you have $45,101 in 7.6 years.... To account for the lost earning potential of that money is a big deal.

For $270 a month in electricity bills I get to make $20k in excess earnings in 7.6 years. After the 7.6 years you get to invest that $270 a month and you will eventually pass me since I still have a payment, but I have a big head start.

 

[WrightGuy821]

The math is rather simple to figure out cost versus money saved. Mississippi gets a ton of solar energy for 9-10 months of the year in Starkville which is more than enough to offset your entire bill in the state. My system would cost 50k to replace my entire usage including the necessary batteries. 50k * .7 due to the tax credit you receive is $35k. I currently use 2259kwh per month with 4 County power with a bill around 300 per month. That puts my system at a 9.72 years payback, but over the life of the panels and battery cycle charge limits, it would save me $54,000 without even talking about increased cost of electricity over the next 25 years.

Now, if I just invested that money in the S+P over the next 25 years, my balance would be around $400k, assuming a double every 8 years. ±

So yes, the solar array will save you money over the 24 year life span, but investing the money would save you considerably more. But that is a different conversation.

The main problem with this way of thinking is that most people don't have the $54k just laying around they have to finance it. Taking out a loan and investing the money is probably not very wise.

 

[maroonmadman]

I was at Costco yesterday and they had 100 watt panel with charge controller for $99. No battery or inverter. Can't remember the brand.

 

[Podgy]

Factor in repairs as well and research who is installing them. Things break, ours did and caused roof damage, which was quite expensive. I recouped some of the loss by selling everything. This was years ago when we recouped our initial investment because of great federal and state tax incentives/breaks. In-law has his in the yard but a hurricane damaged some of them and left him with a huge repair bill. His engineer brother and a handyman saved him a ton of money by doing the repairs. Another bad install, I suspect, caused the damage.

 

[BoDawg.sixpack]

What about damage from hail? Are they replaceable under your homeowners insurance?

 

[eckie1]

What about damage from hail? Are they replaceable under your homeowners insurance?

That depends on how you came about having them installed. A lease would cover everything, since they are bending you over coming and going…. But, even the purchase plan I’ve been proposed would include insurance. I also asked my insurance agent about it, and he said if I need it on my homeowners insurance it would only be $300 for the year.

 

[eckie1]

I nixed the leasing option, and discussed others. This company guarantees 90% of the proposed output of the panels, and if it falters they pay the difference. They’ve said my panels will produce virtually all my power bills outside of extreme usage months. Even then, my power bill would be hardly anythjg

The big difference is that here in TX, we have our own power grid and it’s all deregulated. So, it’s something to keep any eye on year to year. Oncor is the statewide provider, but many companies can sell it with many different plans and stipulations.

This is basically locking in at a certain fixed rate a month. Oncor will pay me back every year for what I supplied to their grid, which should be enough to cover at least a couple payments a year. It’s a fixed payment that’s not subject to the kWh increases that come every time you renew your contact, and the monthly bill would be nothing most months.

I was just checking my power statements. Even in the cold months, my payment wouldn’t be far off from what I pay now. And, the price for kWh will only go up and up and up in the future.

I’m really considering doing it, but want to get some other quotes.

 

[eckie1]

I was at Costco yesterday and they had 100 watt panel with charge controller for $99. No battery or inverter. Can't remember the brand.

Harbor Frieght has them, too. Crazy.

 

[PooPopsBaldHead]

I nixed the leasing option, and discussed others. This company guarantees 90% of the proposed output of the panels, and if it falters they pay the difference. They’ve said my panels will produce virtually all my power bills outside of extreme usage months. Even then, my power bill would be hardly anythjg

The big difference is that here in TX, we have our own power grid and it’s all deregulated. So, it’s something to keep any eye on year to year. Oncor is the statewide provider, but many companies can sell it with many different plans and stipulations.

This is basically locking in at a certain fixed rate a month. Oncor will pay me back every year for what I supplied to their grid, which should be enough to cover at least a couple payments a year. It’s a fixed payment that’s not subject to the kWh increases that come every time you renew your contact, and the monthly bill would be nothing most months.

I was just checking my power statements. Even in the cold months, my payment wouldn’t be far off from what I pay now. And, the price for kWh will only go up and up and up in the future.

I’m really considering doing it, but want to get some other quotes.

If you want it, get it. For reasons like energy independence, hedging, and environmental stuff... But if you are truly interested in saving the money don't listen to what somebody selling the system is telling you the payback period is... You have to figure it out yourself. You must make sure you are looking at the discounted payback period not a simple payback.

You need to run a discounted cash flow analysis on the investment. Your break even point is not when you make back what you spent on the system with electricity bill savings... It's when you make back the system cost plus the lost earning potential of that spend.

If I were to spend $30,000-50,000 on solar right now, it's not coming out of my electricity bill savings account that is all cash with no earned interest. It's coming out of the stock market. At $.13 per KWH it would take a very long time to payback my lost principle and earnings. Financing would be even worse.

 

[ChE1997]

Not sure how new these GAF solar shingles are to the market - https://www.gaf.energy/timberline-solar/
Saw a show on Roku where they put them on a house in CO and they power the entire home. They nail down over shingles using roofing tacks and they connect to each other with a simple connection. You only need to a couple of lines through the roof for power so less intrusion to the decking. Not sure of cost or if they are being installed in MS.

Thanks for this. I've been wondering when more flush mount panels would make it to market.

 

[ChE1997]

When you calculate payback you should include the loss of potential gains from investing that extra money.

If you buy a $25,000 solar system it takes you 7.6 years to save $25,000 in electricity. If you invest $25,000 in the S&P you have $45,101 in 7.6 years.... To account for the lost earning potential of that money is a big deal.

For $270 a month in electricity bills I get to make $20k in excess earnings in 7.6 years. After the 7.6 years you get to invest that $270 a month and you will eventually pass me since I still have a payment, but I have a big head start.

If doing the math that way, are you deducting what you spend on electricity for the 25 years from the compounding? Or adding in the extra value of the solar system to the House value?

 

[ChE1997]

If you want it, get it. For reasons like energy independence, hedging, and environmental stuff... But if you are truly interested in saving the money don't listen to what somebody selling the system is telling you the payback period is... You have to figure it out yourself. You must make sure you are looking at the discounted payback period not a simple payback.

You need to run a discounted cash flow analysis on the investment. Your break even point is not when you make back what you spent on the system with electricity bill savings... It's when you make back the system cost plus the lost earning potential of that spend.

If I were to spend $30,000-50,000 on solar right now, it's not coming out of my electricity bill savings account that is all cash with no earned interest. It's coming out of the stock market. At $.13 per KWH it would take a very long time to payback my lost principle and earnings. Financing would be even worse.

I don't know how you justify buying anything if that's how you do the math.

That said. I have not pulled the trigger myself as I cannot get the payoff period to where it makes sense. (12-18 years) I'm only paying $0.10/kWh, and I won't be in this house that long.

 

[LordMcBuckethead]

I don't know how you justify buying anything if that's how you do the math.

That said. I have not pulled the trigger myself as I cannot get the payoff period to where it makes sense. (12-18 years) I'm only paying $0.10/kWh, and I won't be in this house that long.

That is key. How long are you going to live in your house. If it is the house you are going to die in, it makes sense to do solar. If you are using your house as a stepping stone to a future house (family changes needs change) type of thing, then it makes zero sense to do solar.

 

[PooPopsBaldHead]

I don't know how you justify buying anything if that's how you do the math.

That said. I have not pulled the trigger myself as I cannot get the payoff period to where it makes sense. (12-18 years) I'm only paying $0.10/kWh, and I won't be in this house that long.

When you buy a car or house you make that exact decision effectively. You decide to pay cash, finance, or lease/rent. When you decide to buy vs lease you say I am willing to fork over more money now and/or pay more monthly in order to be free and clear of any payments at a future date. You don't run a DCF, IRR, or NPV on most big purchases because they are usually as much about emotions as money... Otherwise we would all live in 2 bedroom duplexes and drive Toyota Corollas as they would pencil out way better than the nice house with a pool on acreage or the Jeep Wrangler.

Those with the means often forgo paying cash for a home in favor of financing because they know they can earn more on their investments than they can save in interest expense buy buying in cash. The same with vehicles. They don't run a DCF on it, but they figure it out with common sense. In a well run business, we absolutely run DCF models to decide whether to buy new equipment or other capex projects. In business it's almost always about the profits and rarely emotion.

I personally don't have a lot of emotion about my electricity. It's strictly a business decision. I want it cheap and reliable. Solar systems are extremely illiquid assets. Much like a pool. If you have to sell the family home to get any liquidity out of an asset, that's no bueno... One difference between the pool and solar is my big boobied neighbor won't likely come over in her bikini and layout next to my solar panels.

If I can rent electricity for $250 a month instead of buying it for $30,000, that's great. I could take that $30 k and buy some Apple stock, take the family to Hawaii, and buy a shìtload of whiskey that all make me happy. In 10 years I have $30+ k of Apple stock, cool photos of the family in Hawaii, and a severely compromised liver. You have no electricity bill and what looks like a dead decepticon on your roof. But I bet we both die before my electricity bill dwindles that Apple stock down to zero.

ETA... May sell some apple stock to take the big boobied neighbors daughter to Hawaii in year 12 after the wife leaves me for all the drinking... Unless she's over at your place drooling over your energy independence of course

 

[ChE1997]

When you buy a car or house you make that exact decision effectively. You decide to pay cash, finance, or lease/rent. When you decide to buy vs lease you say I am willing to fork over more money now and/or pay more monthly in order to be free and clear of any payments at a future date. You don't run a DCF, IRR, or NPV on most big purchases because they are usually as much about emotions as money... Otherwise we would all live in 2 bedroom duplexes and drive Toyota Corollas as they would pencil out way better than the nice house with a pool on acreage or the Jeep Wrangler.

Those with the means often forgo paying cash for a home in favor of financing because they know they can earn more on their investments than they can save in interest expense buy buying in cash. The same with vehicles. They don't run a DCF on it, but they figure it out with common sense. In a well run business, we absolutely run DCF models to decide whether to buy new equipment or other capex projects. In business it's almost always about the profits and rarely emotion.

I personally don't have a lot of emotion about my electricity. It's strictly a business decision. I want it cheap and reliable. Solar systems are extremely illiquid assets. Much like a pool. If you have to sell the family home to get any liquidity out of an asset, that's no bueno... One difference between the pool and solar is my big boobied neighbor won't likely come over in her bikini and layout next to my solar panels.

If I can rent electricity for $250 a month instead of buying it for $30,000, that's great. I could take that $30 k and buy some Apple stock, take the family to Hawaii, and buy a shìtload of whiskey that all make me happy. In 10 years I have $30+ k of Apple stock, cool photos of the family in Hawaii, and a severely compromised liver. You have no electricity bill and what looks like a dead decepticon on your roof. But I bet we both die before my electricity bill dwindles that Apple stock down to zero.

ETA... May sell some apple stock to take the big boobied neighbors daughter to Hawaii in year 12 after the wife leaves me for all the drinking... Unless she's over at your place drooling over your energy independence of course

When I buy a house, I know I have to have Shelter and I want to own something at the end, and not just pay money. I don't look at the break even calculation vs renting minus maintenance, and expenses. Nor do I calculate how much extra I could have earned with the down payment of 5% vs 20%. I think way more about the schools, and commute or aesthetics. I think I'd be ahead if I'd sunk the $20,000 down payment I made in 1998 in Apple stock vs the house I bought or I could have put it in Worldcomm or Enron and have far less.

Same with a car. I have to have one so I buy what makes sense to me.

I think about electricity the same way, I have to have it. And if I can get it where it's lower cost, I change who I buy it from. In Texas, I do that every year. Also in Texas, the grid is going more to **** as we ignore the federal laws to make it more resilient. Solar for me is not there yet, but it's a lot closer than it was even 6 years ago. If it gets to less than 7 years payoff,

 

[Boom Boom]

When I buy a house, I know I have to have Shelter and I want to own something at the end, and not just pay money. I don't look at the break even calculation vs renting minus maintenance, and expenses. Nor do I calculate how much extra I could have earned with the down payment of 5% vs 20%. I think way more about the schools, and commute or aesthetics. I think I'd be ahead if I'd sunk the $20,000 down payment I made in 1998 in Apple stock vs the house I bought or I could have put it in Worldcomm or Enron and have far less.

Same with a car. I have to have one so I buy what makes sense to me.

I think about electricity the same way, I have to have it. And if I can get it where it's lower cost, I change who I buy it from. In Texas, I do that every year. Also in Texas, the grid is going more to **** as we ignore the federal laws to make it more resilient. Solar for me is not there yet, but it's a lot closer than it was even 6 years ago. If it gets to less than 7 years payoff,

I consider myself exposed to stock risk more than enough via my 401k and private accounts. Buying even more stock rather than some other investment may look good on paper when considering past returns...but that won't help me any if there's a substantial correction. And stocks are historically pricey right now. Something that reduces my future spending may be a great hedge, especially as the price of that spending may go up. Diversification is a good thing.

Buuuuut, I live on the coast. Hurricane risk kinda takes the juice out of rooftop solar. When I build my final home soon I plan on including wiring up to where a gondola or greenhouse may go, and may put panels over there as a hedge one day. It's as much a prepper hedge as a financial one.

 

[eckie1]

If you want it, get it. For reasons like energy independence, hedging, and environmental stuff... But if you are truly interested in saving the money don't listen to what somebody selling the system is telling you the payback period is... You have to figure it out yourself. You must make sure you are looking at the discounted payback period not a simple payback.

You need to run a discounted cash flow analysis on the investment. Your break even point is not when you make back what you spent on the system with electricity bill savings... It's when you make back the system cost plus the lost earning potential of that spend.

If I were to spend $30,000-50,000 on solar right now, it's not coming out of my electricity bill savings account that is all cash with no earned interest. It's coming out of the stock market. At $.13 per KWH it would take a very long time to payback my lost principle and earnings. Financing would be even worse.

This is where we diverge…. My roof can steal 120 kWh from the sun a day on average, and in the past 2 years I don’t have a single day in which I’ve consumed that much. Not even this ungodly summer. I also run a fixed speed pool pump every day, and if that guy ever goes out it will be replaced with a variable speed pump…. Short term investment for long term savings.

Long story short, I will have zero lost earnings potential because I was gonna pay a power bill anyway. My average bill will be about what I pay in the winter. When the panels are paid off, I’ll be making pure profit.

 

[beachbumdawg]

This is where we diverge…. My roof can steal 120 kWh from the sun a day on average, and in the past 2 years I don’t have a single day in which I’ve consumed that much. Not even this ungodly summer. I also run a fixed speed pool pump every day, and if that guy ever goes out it will be replaced with a variable speed pump…. Short term investment for long term savings.

Long story short, I will have zero lost earnings potential because I was gonna pay a power bill anyway. My average bill will be about what I pay in the winter. When the panels are paid off, I’ll be making pure profit.

general commentary

In your calculations, are you all taking into account the degradation of both the panels and batteries over time?

on batteries:
Did you get a guaranteed degradation curve for the battery? Looking at 1-3% degradation annually
Fire suppression system?
what is the T delta for gas venting and thermal runway (greater the better)

 

[eckie1]

general commentary

In your calculations, are you all taking into account the degradation of both the panels and batteries over time?

on batteries:
Did you get a guaranteed degradation curve for the battery? Looking at 1-3% degradation annually
Fire suppression system?
what is the T delta for gas venting and thermal runway (greater the better)

For this proposal, the panels are warrantied for 25 years. I’d be responsible for hosing them off, but that seems to be about it. They’re guaranteed to cover 90% of the average daily proposal for the duration.

I’m not thinking I’ll go for any battery backup. We live on a grid that’s not subjected to planned outages. We never lost power during the 2021 fiasco, while the adjacent neighborhood and most of my town did.

I’ve not heard anything about fire suppression. I have another firm coming out next week and I will be approaching this with many more questions than I had before.