December 17, 2019

Solar Energy Isn't Free Energy

One of the things I used to admire about folks who are off-grid is that they have no electric bill. Many of them say it themselves, they love the financial freedom of not having to pay for electricity. Still, we all know there are costs involved, and some people might be inclined to ask how long it will take for the system to pay for itself. A low-end off-grid system might cost roughly $35,000 not including shipping, installation, and interest if buying on credit. Neither does that include backup, i.e. a generator. The average American electric bill is said to be $104 per month. Do the math, and you'll likely agree that it takes more than a monetary advantage to go solar.

For some people it's a sense of environmental responsibility. For Dan and me, the motive is food preservation. Since we rely more on what we grow than on a grocery store, this is important. The cost of a year's worth of groceries more than offsets the system paying for itself. We've spent roughly $2450 on it, so compared to having to buy all of our groceries, our little system will "pay for itself" in about three or four months. Savings on the electric bill will be lagniappe.

Now that we are in the midst of the project, however, I see something I didn't consider during my feasibility study—eventual replacement costs.

Having recently purchased our batteries, this is forefront in my mind. Our solar panels should last 25 to 30 years, but flooded lead acid batteries average about five years; longer if we take good care of them—shorter if we make mistakes. The fact of the matter, is that we have to be ready when they need to be replaced. Our income is low enough that we must budget for everything, so I need to take this into account now.

What am I looking at for replacement cost? Our six batteries totaled $880, with $100 of that for the core charge since we didn't have old batteries to trade in. If the batteries last 5 years, and I want to have $780 available for replacements, then I need to save $13 per month. Because prices always go up instead of down, it would probably be wise to bump that up to $15. If we want to upgrade the battery bank—in terms of battery type, amp-hours, or both—then we need to set aside more.

We could have bought a different type of battery, one with a longer lifespan, but these come with a heftier price tag. As it was, we did the best we could, and I have no complaints about that. I would be curious if the cost per year for different battery types is comparable to $13 a month, but for now, that's a moot point.

Of course, I'm curious about how much lower our electricity bill will be once we get the freezer (and hopefully fridge) on solar. Will it be enough to offset the savings for replacement batteries? Time will tell! Either way, our ability to preserve our harvest without being dependent on the grid gives me great peace of mind. And that, is priceless.


Retired Knitter said...

Peace of mind is, indeed, priceless. To lose all of a harvest is to lose more than just the food that spoiled. It is to lose all the man hours and sweat equity it took to create that harvest. And "going off the grid" is more than just about saving money. It is about independence and a life style. All those intangible elements must be considered as well.

Ed said...

Another factor I see people neglect to account for is that solar panels degrade with time producing less electricity. I think newer ones are down to losing less than 1% of their production capacity a year but older panels were much higher. So while the panels may still be working 25 years down the road, you are producing a lot less electricity and at the rate society's been going, using a lot more. So like you said, you are forced to upgrade your panels sooner, add more panels or add more batteries for storage, all for a cost.

Leigh said...

RT, all of those things are part of the reason we think it's worth it. :)

Ed, all of the components will eventually need replacing, which has got me wondering if there isn't another way. We don't have a generator, but that's another one. People just beginning looking into solar would do well to research how long each component will last.

Cockeyed Jo said...

One factor you are forgetting about going off grid with solar, you can actually make your electric meter run backwards by having the excess energy going back into the system. The electric company will be paying you (if yours allows for it). We actually did this on my old homestead. Every quarter we got a sizeable check that helped pay for our $25K system.

Maintenance and replacements costs are not only batteries. We had a hurricane brush by us and it damaged several panels also.You should be factoring in that too. Keep $45 a month to cover. That's what we did for every third panel. The glass scratches over time.

You should know how much your electric bill will lower. You know how any kwph that equipment pulls. Just calculate it out.

Ed said...

I know a few people who have installed mini wind turbans for their house. While there are still maintenance costs, their electrical output doesn't degrade over time. I also know a person with a generator in a small spring that does pretty well since it doesn't rely on batteries or storage. But it does require a constant water source and a lot of fiddling to keep it running in a wet environment. It also doesn't provide a lot of energy but I suppose could be scaled up with more generators.

I still think solar is a great source of providing off the grid power and may eventually pay for itself in the long term. I just don't think it can work for short term payoff that many tout unless of course you add other things to your justification such as protecting an off the grid food source like what you produce. It is hard to put a number on that.

Leigh said...

Jo, that's correct about other parts of the system. I just used batteries for my example to make my point.

Selling electricity back to the utility company only applies to grid-tied systems rather than off-grid. It's a very attractive idea for a lot of folks. Dan and I will never get to completely off-grid, so that's not a decision we'll ever have to make. Out of curiosity, however, I took a look at the contract our utility company requires of customers tying into the grid. I highly recommend that anyone considering this go to their electric companie's website and download a copy of their contract. Ours is very interesting.

1. It limits the size of the system to 90% of the customer's distribution service rating. Fines apply if it's exceeded.
2. The customer's homeowner's insurance policy must carry liability coverage with a minimum of at least $100,000 per occurrence of bodily injury and/or property damage.
3. The company agrees to buy excess electricity but is not required to.
4. The company can require the customer to reduce or interrupt production.

Some utility companies have started adding extra fees to home energy producers. That's something else folks should research.

The gentleman we bought our solar panels from was an installer. He told us that our utility company had the reputation for being the least solar friendly in the state--very difficult to work with. That being said, others may find their electric companies much easier to work with and having better terms.

Ed, interesting about the wind turbans. I don't think we get enough wind here for that, though. But I wish we did. Ditto for hydro.

I agree one has to have a long-term view for alternative energy. And in the meantime, we're looking to find ways to back up our backup. :)

wyomingheart said...

I completely agree with you, Leigh, in the food preservation need. We are also dependent on freezer space with our bountiful harvest each year. The idea that we have a year worth of groceries in the freezer is a life saver for us, and preserving it is priceless. This information you have shared with us is critical to that self sustaining life we desire. Thank you!

Anonymous said...

I went solar last November, and I love the fact that the electric company now owes ME money! Like you, I try to preserve as much of our summer harvest as I can, and I stuff the freezers full to capacity. Thankfully, my sweetie bought me a whole house generator as a housewarming gift when I first moved in, which is such a comfort, especially on a snowy day like today!

Rain said...

I love how you think Leigh. When you think of battery replacement on a monthly savings basis, you can really see the savings in electricity. Our electricity bill, I think I've mentioned it before, it over $300 a month, it's insane and ridiculous because we just don't use that much electricity. It's all heat. A solar set up (done frugally like you and Dan did) would be much more cost-efficient for us for sure.

Leigh said...

Wyomingheart, you're welcome! Dan and I have a motto, "Food First." Any time we have decisions or choices to make, we try to focus on just that. It helps us set our priorities.

Debbie, what a wonderful gift! Lucky you! Dan would love to have a generator, but that's still out in the future somewhere.

Rain, even setting aside replacement costs for batteries and the rest, it certainly seems like you would be a whole lot better off. Or if you could at least use wood heat, that would help. Without our wood heater, our electric bill would be pretty outrageous too.

Cozy Thyme Cottage said...

I didn't realize it would be that expensive but like you say the peace of mind of your food not being ruined is worth a lot. Nancy

Leigh said...

Oh Nancy, nothing is cheap! And it seems like prices for all the components have only gone up over the years. That always seems to be the case, doesn't it? Especially, when an idea is popular.

Quinn said...

I am watching in a sort of spellbound awe as you and Dan undertake this particular adventure, Leigh! Two friends have been "going solar" for ages now, and I don't want to ask if they are up and running because I am afraid the answer will still be "not yet"!

Leigh said...

Quinn, I admit this is going much slower than I had hoped. (And my blog posts are somewhat behind that!) There is lots to be aware of and be careful with. We spend time doing research, discussion, and planning in between each step. And of course, the weather has to cooperate! Hopefully, you're friends will get theirs going soon.

Toirdhealbheach Beucail said...

Peace of mind matters. I think the reason solar is so often disappointing to people is that it seems highly touted as a "solution" to high energy bills. The infrastructure and replacement costs are not considered (as they really should be).

That said, it can make a certain amount of sense. Wind does too - water, for that matter, if you have a location that supports it. It really becomes more of a question of the need, the budget, and ability to actually meet the need.

Leigh said...

TB, I think one thing that solar does is to put a sharp focus on how much energy it really takes to do the things we are used to doing. I've read more than one off-grid person comment on checking the state of things first thing in the morning in hopes of having enough to heat water for morning coffee! Sometimes there isn't enough so that the day doesn't start off very well. :o

I wish we did have other sources to tap into. We have wood, and Dan has plans for a wood gasifier, so that might be a future possibility.

tpals said...

I added solar to protect my son's insulin supply in case of extended power outages. At the time I had an income to make it feasible. It's set up to power the fridge, freezers and furnace but is useless if the panels are buried in snow. ;)

I didn't go with grid-tied because here the power company can buy the excess at a tiny fraction of what they charge and of course it would be shut off in case of an outage for their safety. I'd rather use it all myself.

Leigh said...

tpals, that was very wise of you. Medications requiring refrigeration need a backup. Good point about snow! We don't get a whole lot of snow, but we do get some. Makes me glad our solar panels are close to the ground.

Kelly said...

Of course we're still on the grid, but we definitely did our research and put the pencil to it before making our final decision. I'm still confident we did the right thing.

I smiled at your use of the word lagniappe. That's one I don't expect to hear much outside my part of the country. ;)

Su Ba said...

You're right on when you say that solar electricity isn't free electricity. As you know, hubby & I are off grid and have been since 2004. So over the years we've had our share of expenses, primarily new batteries. I usually tell people who are considering living like us that our electricity isn't free....we pay for it in chunks, with most of it being up front installation. Luckily we can do our own maintenance and repairs, or else we'd be spending money on servicing. Sounds like you & Dan will be able to do your own servicing too.

Leigh said...

Kelly, I lived in Louisiana for over nine years. :)

I like that you're confident in the choices you made. That means you did a good job researching them and how they'd affect you! Do you have a backup?

Su, that's an excellent way to put it; paying for your electricity in chunks. Yes, we'll maintain it ourselves. That's the way our budget works! If we had to rely on someone else it wouldn't happen. :)

Kelly said...

For decades we'd hook up our welding unit (gasoline powered) when we had lengthy outages, but when we installed the solar we went ahead and got a natural gas generator that will automatically come on in an outage. I don't know why we didn't do it sooner!

I figured you had to have some connection to this part of the world! ;)