When the utility company said natural gas prices were increasing 250%, I got a quote for a solar/battery system that would only use grid electric when needed. $14,000 would supply 100% of our average electric plus have four days of backup. The ROI was 12 years, but if the natural gas prices did increase 250% AND I switched to electric heat, the ROI for a larger system was only 5 years.

There was no reason to replace the furnace, natural gas only increased 200% so far and may drop as temperatures increase. Still, if the furnace needs replacement it may make sense to go electric and install solar. GAF solar shingles just came out and might make sense if one needs a new roof.

If I had the roof space I'd certainly consider it--mainly for when the power goes out. Running on a backup generator when that happens is no fun.

But, being only a 1300+ sqft. ranch, and a hip roof, incl. the garage, there just plain isn't enough space up there for a solar array big enough to produce much--esp. being in the upper midwest.

quote:

Originally posted by ensigmatic:
If I had the roof space I'd certainly consider it--mainly for when the power goes out. Running on a backup generator when that happens is no fun.

But, being only a 1300+ sqft. ranch, and a hip roof, incl. the garage, there just plain isn't enough space up there for a solar array big enough to produce much--esp. being in the upper midwest.

And you'd have to worry about keeping it snow-free in the winter. I don't think roof mounts are very practical up north.

quote:

Originally posted by Gustofer:
And you'd have to worry about keeping it snow-free in the winter. I don't think roof mounts are very practical up north.

I don't think they're very practical anywhere. Seems like a great opportunity to get a roof leak.

The sides of my roof face east and west, plus my western neighbor has a huge sycamore. Not an option for me.

quote:

Originally posted by Gustofer:
And you'd have to worry about keeping it snow-free in the winter. I don't think roof mounts are very practical up north.

One of my best friends just had solar installed for his property in northern lower Michigan. The panels are installed on the roof of his rather large pole barn.

They set the angle of the panels to the winter angle. They're far more vertical than I would have expected, but the sun angle does get pretty low, even here in S.E. Michigan, in wintertime.

They're so vertical I doubt they'll collect much, if any, snow.

TBH: My bigger concern would be snow accumulation and load behind the panels, but he seems unconcerned. I guess he'll find out

Many rural homes and businesses in Iowa have solar panels on stands separate from the buildings. If you have the space for it, those make sense. Easy access and maintenance plus easy to clean and adjust angles based on season.

quote:

Originally posted by sig2392:
ROI on solar is 12 to 30 years depending on the system. The average American moves every 5 to 7 years.

Most people will never see their ROI.

Sif2392: May I ask where your ROI number came from?

The technology, yield, and manufacturing techniques, like everything in high tech, is improving every year. There is something called the EPBT (Energy PayBack Time) which is how long the panels have to sit in the sun before the energy required to make/install the panels is recovered.

EPBT is about 4 years now, but Thin Film is advancing every year. Kind of like a Moore's law, only for solar.

Again, the present numbers for multicrystalline panels are about 4 years, and not 12 to 30 years. 12 to 30 seems like where the technology was at a long time ago, when things were very different in the technology / manufacturing / yield areas. Of course, companies have to make a profit along the way, but still 12 to 30 seems high.

Disclaimer. There is a large YMMV with solar. Anchorage is far different from New Mexico. Dust, snow, and even bad installations where to panels are pointed east and not south (in the USA) -- yes, I've seen this.

Sucks when someone's roof faces east, and someone wanted to install solar anyway. That's simple malpractice IMHO.

Check here: https://www.nrel.gov/docs/fy04osti/35489.pdf

quote:

Originally posted by sig2392:
ROI on solar is 12 to 30 years depending on the system. The average American moves every 5 to 7 years.

Most people will never see their ROI.

Personally, I find the ROI argument on solar rather silly unless your goal is to make money off of it from the power company.

Most (if not all) of the people I know, myself included, desire solar or other alternative power in order to have juice when none is available. When you need it and have it, cost really isn't an issue. You're paying for peace of mind and, frankly, for your survival. What's that worth?

Many people (including many here) spend $5-10K for whole house generators that rarely get put into service. Does ROI get argued for those? I never hear it.

$30K (before taxes/rebates) was too big of a check for me to write for what was offered, but I am shopping around for a better price as I want the peace of mind. If I could find an offer like bryan11 got I'd jump on it.

$50K for a panel system, here in Fl to generate 100% power coverage, now that means in off months we generate credits and high use months we would use the credits. 70+ panels, on the roof, $50K less Government Taxpayer credits to be used against paid income taxes.

So it's still $50K.

Financed option is $500 a month for 10 years, which is more than we pay, we're at $300 average monthly.

And that's without battery as we'd need 4 powerwalls to run the house fully, another $40K.

Would solar be great and no power bill? Sure but in FL we don't get the taxpayer funded breaks you do in CA or MA that shortens payback by charging your neighbors for your install.

The issue for these things in a R state, is you can't welch off your neighbors income to pay for your solar.

There are also laws regarding increased insurance coverage for solar in FL since we have the occasional hurricane that could send them flying around.

You also have to pay a monthly fee to be connected to the grid with Solar and sell back your power to the companies here, no selling on the open market like in other states, again, reducing the ROI potential.

The only thing you might consider solar for is a hedge against power cost inflation over the next 20 years. Having it may just protect you from having a power bill that's greater than your mortgage payment in 2040...

I have an 11 page thread here about my own Tesla Solar panel install.

https://sigforum.com/eve/forum...935/m/8520036274/p/1

Short version is that the economics maths out for me at the individual level. Whether or not it works out at the macro level for the entire planet trying to be "green" is not my concern. I like "green" in that I like green dollar bills in my wallet.

My system cost $12,216.21. At a "conservative" power bill savings of $180/mo, my breakeven is 5.5 years, not counting the increase value to my home. Each year thereafter, I save an additional $2160 a year in power costs. If I keep the system for (only) 15 years, I'll have saved $20,340. The system is warranted to last 25 years, but I figure 15 years from now something better might come along.

If we're talking opportunity costs, $12,000 invested at 6% interested will be worth $53,579.45 at 25 years (compounded monthly).

$12,000 invested into Solar will save $180 a month, which, if the savings are invested at 6% will be worth $124,738.91 at 25 years.

All in all, I am happy with my investment. I was conservative with my estimates, and my system was over-sized by about 20%. Additionally, my system is producing more power than anticipated, and I have added an electrified vehicle to utilize my excess production. Although I do not yet have a full year of data, I estimate that I will in fact be generating $220 in electricity savings a month, which moves my repayment period up to 4.6 years. My return on investment will be $152,458.67 in 25 years.

Additionally/alternatively, with the new car, I'm saving approximately $1800 a year in gas (when it was only $4 a gallon here, not the $5.50 it is now) and am instead soaking up excess solar output ("free power"). The math is a little more complex than that, because you'd have to take into account the added cost of the electrified vehicle over the non-electrified version, but I'm still confident I'm coming out ahead.

For me, these won't make sense until the monthly payment to install a system (panel costs, installation costs plus additional insurance rider for panel installation plus grid connection fee if applicable minus any credits generated) is the same or lower than my existing monthly electric bill.

I can put that money to better use in the market.

As someone mentioned, the technology is continually improving so at some point a system will start to make more sense, especially as energy storage technology also continues to improve over time.

My main takeaway from going through the process is to aggressively shop on price.

I received multiple quotes in the $20k to $30k range for similar or less output to my $12k system.

Overspending on the panels really messes up your ROI.

If you can spend $12K on a solar sytem (w/ batteries) or $10K on a generator that still requires fuel that costs money, which is the better investment?

quote:

Originally posted by ensigmatic:
If I had the roof space I'd certainly consider it--mainly for when the power goes out. Running on a backup generator when that happens is no fun.

But, being only a 1300+ sqft. ranch, and a hip roof, incl. the garage, there just plain isn't enough space up there for a solar array big enough to produce much--esp. being in the upper midwest.

Most of the typical residential systems go dead when the "grid" goes down. Some may be accessorized to work, but in general, they just go dead, so not always a back-up solution, unless you add some additional hardware.

Don't know about Michigan, but AVERAGE you get about 1100 kWh/M^2 per year for a typical install. You can calculate from there.

basically today's technology gives you about 230 watts per square meter when direct sunlight is hitting it. As with all things solar, YMMV.

quote:

Short version is that the economics maths out for me at the individual level. Whether or not it works out at the macro level for the entire planet trying to be "green" is not my concern. I like "green" in that I like green dollar bills in my wallet.

Its an individual thing, you have to cost it out for the buyer, depends on price of system, amount of energy you use, cost of power in the state you live, government graft programs in that state, the ability to resell excess in the aftermarket vs being cobbled to the state power grid. The direction your roof faces (S is best) all kinds of factors.

Some states it makes a lot more sense and recovers quickly. I just don't see it working out and live in a state where it should be advantageous financially. Go figure.

quote:

Originally posted by Gustofer:
If you can spend $12K on a solar sytem (w/ batteries) or $10K on a generator that still requires fuel that costs money, which is the better investment?

If we're going to do apples to apples, it would be $25k-ish for a solar system and a pair of Tesla power walls capable of handling the peak load required to start an AC system for a 4000 sqft house.

Even at $25k for solar vs $10k for standby generator, solar wins in my opinion because it is generating savings for you every single day, not just the days the power goes out.

quote:

Originally posted by Gustofer:

Personally, I find the ROI argument on solar rather silly unless your goal is to make money off of it from the power company.

Most (if not all) of the people I know, myself included, desire solar or other alternative power in order to have juice when none is available. When you need it and have it, cost really isn't an issue. You're paying for peace of mind and, frankly, for your survival. What's that worth?

Many people (including many here) spend $5-10K for whole house generators that rarely get put into service. Does ROI get argued for those? I never hear it.

$30K (before taxes/rebates) was too big of a check for me to write for what was offered, but I am shopping around for a better price as I want the peace of mind. If I could find an offer like bryan11 got I'd jump on it.

There's no way you can compare $30K spent on a solar system to $1K or less spent on a generator. And the generator is the way to go. Take the other $29K and put it in the market and at the end of the ROI period you'll still have your generator, power when you need it and $200K or so in stocks waiting for your retirement.

The way to go is obvious.

I think ROI is being used for the Break Even Point, and I think because that point is many years, the calculation would not be simple division, because of the money involved over a period of time, combining inflation, borrowing, and opportunity cost rates, and individual scenarios, age, etc. But I'd imagine the people who know best are the companies selling those systems, and they're probably not gonna give you the straight skinny. Part of the problem I think is that solar and wind is deeply embedded in political argument and ignorance, that for most of us, me included, the truth is difficult to know in a more general sense for most people. But so far based on this conversation, it doesn't sound like a good idea more often than not. If you're a young millionaire and you're a nerd and you're a tree hugger, it's probably a very good idea. Or for other conservative people they may like to spend the money on solar just for the hobby factor of it all for lack of a better term.

quote:

Originally posted by Flash-LB:

The way to go is obvious.

The way to go is obvious, if you have a clear understanding of the end goal.

Emergency temporary backup? You are right, get a couple portable generators and an interlock. It's cheap, portable, and good enough.

Standby power for long term off-grid living? Solar + wind + batteries appear to be the way to go, but certainly not because of cost savings. Measure the return on investment here in capabilities purchased, not dollars saved.

Solar to offset your power bill? 100% just a math problem that requires you to think about your cost of electricity vs the cost of installation.

For me, solar to offset my power bill is stupid obvious. Grid power is really expensive, and we have strong sun year round. But, for emergency backup I've still got a little portable generator rather than investing in batteries--the economics of a household battery backup makes no sense to me.