solar power for home

So for my entire life I been hearing how the price of solar is dropping exponentially along with battery price.... so, where does one begin when thinking about buying a complete system for living off the grid? What should it cost?

That is still pretty expensive.
you have multiple things to consider.
Fully off the grid means how much capacity the panels have, storage and how much are you going to burn through.
Some things can be either gas or electric.
But if you are fully off the grid, you are probably out a ways, so you have to consider propane as the source for other fuel choices.

The area you live in makes a difference. How sunny is it.
How much room do you have for panels, vs just the roof. Because just the roof won't get you off the grid.

There are appliances that are specifically rated for lower wattage use.
So that would also include the air handler for your a/c unit if you need one.
hot water heater etc..

You would have to first run the numbers on how much power you need.
Then figure out how much square footage of panels you need to just keep up.
Then you need to know how much extra you need to charge up the batteries and maintain your min due to less sunny days.
Then how much battery capacity you need based on how long you need to keep power for when it is dark, rainy, or cloudy/snowy.

once you get those numbers you can figure out how much it will cost you.

Now companies come around all the time pushing "free" solar panels to supplement the grid where you live.
Those seem to run around 25k, but it isn;'t going to get you off the grid.

Solar isn't the most efficent, or optimum.
you really need wind and solar to have enough that won't break the bank to be fully self sufficent.

We have a solar installer member here ( ft Lauderdale) , and another solar long time user in St Croix, they will be able to address your inquiries.

Pretty sure Montana doesn't see the sun like FL or St. Croix does. Not to mention winter differences. Snow on the panels need removed. Long winter nights up north are also an issue.

Good thing you are here, I'm also sure the two I mentioned above will be grateful and enlightened for that geographical detail.

Another thought would be hydro of you have fall and water supply .
If you are doing new construction there are all sorts of energy efficiency methods you can incorporate.
Geo thermal
solar orientation
earth insulation of building envelope
solar hot water (big money saver)
12 v lights
If you have a stream and a way to re-route a small impound (tank or pond) of water you can run a pelton wheel.
For full off grid battery storage banks and inverter to get to the voltage you want.
A lot of the first items are relatively inexpensive compared to battery purchase / replacement.
The more alternative and efficiency you build in the smaller battery bank you'll need.
I'd start by building or retrofitting a home to get the most solar gain. Search: Passive Solar Home Design or maybe PS home projects
a start https://www.energy.gov/energysaver/energy-efficient-home-design/passive-solar-home-design

Solar inverters are the most common breakdown point.

Some questions to consider going completely “off the grid” beyond the electric usage return on investment...

Does your solar company offer 24 hr, 365 day repair support? Does that house call come within 1-2 hrs ? Does a governmental agency monitor your solar companies breakdown to restoring power (fix) support time?

Does your solar company include a maintenance program to come out to your house and check your equipment for as long as you are using the solar?

If your solar equipment fails or has an issue, does it automatically sent a message to repairman to come out and make a house visit without you calling?

If you are “off the grid” and have no continuous financial connection with the company that sold you the equipment or any other solar company. Is that maintenance support included with the initial cost of your equipment or is it an additional monthly service/insurance fee?

Someone's got to cover for you

Around here, solar installation outfits come and go like the seasons. I would sure be concerned about depending on them a few years down the road. Same goes for much of the components.

And we have geo-thermal. We are not unhappy with it, but in our climate zone, I don't see how on earth it really makes any financial sense. It is just too expensive to install and any service is also much more expensive.

We would have already installed solar here, but the financial deal with the utility is just plain horrendous. The 2 deal breakers for me is that if the utility power is down, then we are down. And during the summer, typically you produce more power that you consume. That power goes into the grid and you get a credit. But the credit disappears at the end of the calendar year. So you end up giving them your excess power in the summer and then they get to sell you their power in the winter.

The SUN is one heckeva thing to TRULY DIGEST !

Two trivia Qs ... if we could LIGHT OFF all the energy man has ever produced SINCE DAY ONE .. how long would that power the sun ?

If we could harness ALL the solar energy that hits THE ENTIRE EARTH during 24 hours AND COULD PROPERLY store it ... how long would that power ALL OF OUR energy needs ?

Grid connected has best operating characteristics. Use as much self generated as ya can, some times back fill from grid, sometimes sell back.

Cost to install and get turn key depends on buy or lease and kinda oddly like a car. Lease is like no money down but they own the hardware for the first 20 yrs. Less out of pocket but less margin because it's split. Still a long term option. I like cut a good deal, buy it, take 30% tax credit except retired, no income to use it until a few years from now. More out of pocket, much faster pay back and larger long term gain. Roof condition before install should be looked at. Probably pretty easy to pop the racks off for a re shingle but why do it if ya don't have to.

Overall prices have gone down as availability has gone up and technology improved. Monitor / control yer install and connections thru yer app. Boom market for installers, Obama policies helped, local governments are insane. A few years back some sun belt state yanked all incentives / grid buy back mins - totally killed solar as viable and a company or three. Eventually over turned in the courts, check yer local scenario. That was extreme but conditions are subject to change.

Check in your local area for installers and subsidies. I looked into is last year here in Oregon and found that you had to have a large southern facing roof before they would even bother to talk to you. If you have a large southern facing roof then they will provide you with a quote. If your roof is large enough you might be able to put enough panels on it to power your house. Pull out some of your electric bills so you know exactly what you're dealing with in terms of load and cost. You need to qualify for a really large subsidy before it even comes close to making sense.

That reminds me, talking about maintenance.

solar panels lose efficiency due to age. so you have to ask how that works. it is at some point necessary to replace them.
The issue is payback costs don't line up with when they have to be replaced.

Yep, lots of little details like that. CA recently passed a law saying all new houses needed to have solar panels but it was quickly pointed out by a bunch of people that the state of CA fudged the numbers when they claimed it would pay for itself. At the moment it doesn't seem close to paying for itself for most installs. It might be possible with a new house in CA that is designed to be super efficient that a solar array could provide power and eventually pay for itself but I can't see it happening in Montana on a house that wasn't designed for it. Most likely zero chance of that happening.

A friend did a self-install on his own for about 8K to kill his entire winter bill plus some extra.. summer bills are small. Around here depending on utility provider, the payback is as quick as 3-4 years with our crazy summer AC bills.

One neighbor has is house during summer at 68* when it's 100+ out... no bill with his solar. I bet his bill would be 700+ during summer with that indoor temp and AC running 18 hours a day.

Lots of places it doesn't make sense. In the desert here, we have two primary electric providers. One is much more expensive than the other and it makes sense to do solar in their area. The less expensive provider, it's basically a wash for the most part unless you have significant usage, pool spa, water features, huge AC units.

We are asking because 20 acres I want to buy is going to cost a pile to run power company power to it, if I can spend $15,000 and have basically no electric bill for 10 years I will be very far ahead.

It's true, we don't have the sunshine of so cal or phoenix but we can run wood heat, propane heat, LED light blobs and such and run a pretty minimal electric bill., probably gonna do all that anyhow so not like they are extra expenses. The land is mostly sunny, the mountains don't effect sunshine much where it is located. Also we already don't run AC in the summer so that's not even a big deal.

Here is another concept I did not mention trombe wall
I think the more insulation and heat or cool storage you get the better. Also think about extra foundation insulation.
A lot of these items can be done inexpensively when building new.
Montana state has a website resources.

If you are building the house then you can do a lot of tricks to save energy. Extra thick walls, extra insulation, bury the back side of the house into a hill, arrange the house so you get maximum solar heat during the day, etc.

So it's off grid to start with

I think Tesla is running ~$1.49/watt right now. So 8kw => $12k. Add a couple powerwalls and you're around 30k before incentives

If you can do all the research and find the panels and inverters yourself, you may be able to come in cheaper than that.

Getting to 100% from solar all the time might be hard, unless you dramatically oversize it, or are fine with the occasional "day off". A propane generator backup probably wouldn't be a bad thing.

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For my address, Tesla is recommending a 16kw array, and 4 powerwalls. Cash price of $60k, but that's 100% off grid, with 12 days of backup duration

If THIS came with a solar system... I’d consider THAT at my shop ...

look into an outdoor boiler system. It uses very little electricity and you can keep as warm as you please, plus you can heat endless water.

A local guy who runs solar, has found that golf cart batteries work pretty well compared to the purpose made solar battery array. He says buy mid morning he his batteries are good to go for overnight.

You would need a solar powered life support system to handle that.

This is what I would do.

1-Buy a 1,000 gallon propane tank.
2-Generator propane fueled 1,800 RPM 5 to 6 KW. My preference is Onan.
3-Inverter/Charger Xantrex XW6048.
4-Start with one battery bank so 8 batteries 6 volt.
5-Build your own solar panel rack and start with 8 panels 345 watt
6-Solar charge controller
7-Generator start interface
8-Combiner box
9-Wiring and misc.
10- Building to protect equipment. Me I would get a 40 foot shipping container.

Things to always keep in mind. Do not buy cheap or under build. Once up and running you will see what your solar array is doing and you can add to it as needed. That is the main reason to get a larger solar charge controller. Your battery bank you most likely will find that 2 banks of 8 will be optimal. Inverters on 48 volt input use the same energy at idle as a small inverter 25 to 35 watts however they will have a continuous output of 6,000 watts and 12,000 watt surge. Having a system like this will run your house and garage.

Like the two members here I noted from Ft Lauderdale and/or St Croix?

Let me know when you got something beyond obvious to share.