Is solar power worth it? an analysis 12 years after installation


Hi, i’m pete and welcome to just a few acres farm in a lot of our videos. You see this in the background. This is our photovoltaic power system or our solar electricity system, and it’s been going for 12 years.

Now, 12 years in august, in this video, i’m, going to go over how the system works, how its parts and components are put together and how much power it’s made in the 12 years to help you decide whether it Makes sense for you to have solar electricity on your small farm, but before i get started, i wanted to mention that i used to do this in my old life.

One of my expertises was designing uh solar, photovoltaic systems and i actually wrote a book about ending my old job and starting uh the farm and all the things that went along with it in this book called a year and a day, and just a few acres And it’s, a good read i’m, not biased, but that’s.

What i think you can find this book down in the video description and there’s, a link to amazon, where you can buy a copy. This system is 6.2 kilowatts or 6200 watts that’s, its peak power output on a sunny day at noon when the sun is highest in the sky and to start off.

I have to give you a few units that i’m. Going to mention a lot, a watt is a measure of power usage at any given point in time. So, if i turn on an electric hairdryer, i’m using between 1500 and 2000 watts.

If i turn on an old incandescent light bulb, i’m using around 60 watts on average kilowatt hours, are a measure of power used over time? So if i turn something on that takes a thousand watts and i run it for an hour – i’ve used one kilowatt hour of electricity and when you look at your utility bill, you’

Ll see your electricity usage measured in kilowatt hours, i’ve used so many kilowatt hours this month and that’s. What your bill is based on. I know this is a funky view, but this is the best way to see the makeup of the panels.

There are three poles here and each pole has 12 solar panels on it that are side by side and up to down. Each panel is a sharp 170 watt panel. So there’s. 36 total. When you add the three poles up and that amounts to about 6 200 watts 170 times 36.

, since these panels are on poles, we can tilt them seasonally to take best advantage of the sun right now they’re tilted at 30 degrees in the Winter time we tilt them at 60 degrees, so they’re much more vertical and that’s, because the sun’s at a lower lower angle.

In the winter time we tilt them on the equinoxes march 21st and september 21st and tilting them is easy. There’s just a bracket up. Here i get on a ladder undo. One bolt hillary holds the bottom of the solar panel and we tilt it and then fasten it in a different hole up there on that.

Top bracket only takes us about 10 minutes. All the wiring from the different panels is joined together and runs down and the other poles run down underground and they all come together in this box here this combiner box, and then they go into this disconnect.

So we can disconnect the production of the system from out here. If there’s ever an emergency from this disconnect the wires run underground and they run straight over to our garage over here i have kind of a funny story.

We hired somebody to install this and when they went to install the wiring from the panels over there over to the garage, they had to run at 18 inches deep, all the way through here in a trench in conduit, and they used a walk behind, ditch which To dig the trench well, they hit all kinds of stone foundations as they went from one point to the other and they couldn’t, get through the stone with the little ditch witch, so they wound up hand digging a lot of the trench.

So the underground conduit comes around our garage into our wood shed here and there’s, a disconnect on the outside wall of the garage. The inverter is right behind this wall inside this is a sunny boy, 6000 watt inverter and the inverter’s.

Job is to take the dc power that’s coming from the solar panels, which is usually around 300 volts and turn it into 240 volt ac power to run things on our farm. It also matches the cycle and phase of the power coming in from the grid, the utility lines that are connected to our farm, so that we can put power out to the grid when we’re making more than we need now.

This is a really important part of the system. It’s grid connected, which means when we make more power, we send it into the grid, and when we need power, we take it out of the grid. This is different from standalone battery powered systems where the inverter is charging a set of batteries.

This is like using the electrical grid as a bank, so we’re, putting power into the grid. When we’re, making too much and banking it, and then we’re, pulling it out of the bank when we’re, not making enough power and because new york has a net metering law, we pay the same thing As we get back from the utility, it’s, the same cost per kilowatt hour.

I like that aspect of the system, because usually when we’re, making more power than we need it’s a hot sunny day in the summer and that’s. The time when the grid gets most stressed because a lot of air conditioning is being run on the grid and using a lot of electricity.

If i knock on the panel, it lights up and i can see different readouts co2 saved a really big number. After 12 years knock again, current power output, 3 100 watts voltage 271 volts coming in total power produced 82518 kilowatt hours.

How much produces electricity today 4.73 kilowatt hours and back to the beginning from the inverter? The power is fed through this conduit into our garage sub panel and from the sub panel. It makes its way into our house via some more underground wiring.

The wires from the sub panel in the garage come underground into our house. The main electrical panel is in the basement of our house and then from the main electrical panel. Conduit comes out underneath the lawn here and goes to the utility connection meter and yes, there’s, a little bit of man versus nature going on here.

With the vine i like it now, our meter is a little special because it’s, a net metering meter. It has two readouts, one is the power we’ve drawn from the grid, and the other is the power that we’ve put back into the grid, and this is how our electric bill is figured now on to the numbers part.

When we put in this system 12 years ago, it was sized to meet all of our electricity needs on an annual basis, so we would be what’s called net zero, that is in the summer time we would make more electricity than we needed Bank it in the grid and then in the winter time we made less than we needed.

We could pull out from that bank. So, on an annual basis. We were getting all of our electricity in a sense from the solar panels. Although the grid was involved, when we put in this system, it was about thousand dollars, after federal and state incentives and tax credits and to date, this system’s made about eighty two thousand kilowatt hours: electricity, as shown by this electric meter, that runs Off the inverter, the electricity we buy from the grid cost us about 10 cents per kilowatt hour.

This includes supply charges, delivery, charges and taxes. So to date, we’ve made about 8 200 in electricity, so the system’s made about half of the energy it needs to to pay for itself, and the total payback period will be about 25 years.

That’s. An awful long time i know, but i had other reasons for installing the system number one. I thought it was the right thing to do environmentally and from a sort of self-sustainability standpoint number two.

I was in the business of designing these and this acted as a demonstration case for clients. I had its readout connected to the web and wherever i was, i could pull up this performance statistics and current performance and show it to clients.

So if i’m looking at 25 years payback, the question is: can i make money off of this? How long will this system last will last 50 years? Well, there’s, two components number one. The panels will last indefinitely, but the problem with the panels is that they’re subject to something called weathering, and that is when rain and dirt get on them.

Gradually the glass gets microscopic scratches in it and becomes less transparent, so less sunlight gets through to the tune of about a one percent loss per year. So 12 years into this, i’ve lost about 12 percent of the peak capacity of this system.

Through weathering on the face of the panels, the inverter is another matter. It is filled with lots of complicated electronic parts. This inverter was warrantied for 10 years. It’s on year 12. Now i’

Ve never had a problem with it, but we may have to replace it sooner or later. The good thing is that the modern inverters are more efficient than this, so we’ll, actually generate more power off the system with a new inverter when it comes to other upkeep costs and time there really haven’t been any.

I check the inverter once in a while to make sure it’s working and to see what the output is. I tilt the solar panels twice a year there’s, really nothing else. The good news is that solar technology has really come down in price in the recent years now you can put in a system like this for half the price about 8 500 bucks, which means this system would have paid for itself by now in year 12 and Anything else is icing on the cake.

The technology has changed so much now you can buy inverters that are dual mode, so you can either charge batteries with them or connect them to the grid. So you have power during power outages. If you would like, the panels can come with micro inverters in them, where you have a little inverter on the back of every panel and it optimizes each panel’s performance.

So you get more energy out of the system. There’s. So many new developments and here in new york giant systems are going in all the time. These are megawatt-sized systems. In fact, there’s, a farm, a couple miles from us that’s about 500 acres, and there are negotiations to cover that land with solar.

That’ Ll generate a lot of power as to the merits of covering farmland. With solar, well, i’m on the fence about that. If it’s, productive land, i don’t know i feel like solar should be put on marginal or non-productive.

Land is solar power right for you? Well, of course, i can’t answer that i can’ T say that we put it in because it aligned with our values, and we had the upfront money to pay for it. Now, if you don’t have the upfront money to pay for it.

There are different arrangements, you can get low-interest loans to finance it and there’s. Even solar lease-backed programs, where a contractor comes installs the system, and then you pay them for your electricity at a rate that’s less than the utility rate for a fixed number of years and at the end, you own the system, as with everything In life, it all just depends on what you think is important, as i look around us in the way that we’ve built out our farm, we’ve, focused on what we think is important to us and what we think makes A difference in the world and surrounded ourselves with it, so your challenge is to do the same.

I guess thanks for joining me. I hope this was informative and i’ Ll see you next time.