What do you need to harvest the sun?
We live in a solar powered house that includes solar panels on the roof and adjoining tower. When folks come to visit, they often mention their desire to “get some of those”, meaning the solar panels. But most people do not realize that you need more than just photovoltaic panels to use the sun’s energy.
Solar Panels Mounted on our Tower
What equipment do I need to build a home solar power system?
The Solar Panel: to harvest the sun.
The first item you need is the most obvious: The Solar Panel. This is the equipment that captures the sun’s rays and converts them into electricity.
How many Solar Panels you need depends on
- The amount of power you need to produce
- How you choose to wire your system
- What you can afford to purchase
The Inverter: to use the sun.
A second item you will want but perhaps not need is the Inverter. The basic function of an inverter is to change DC power made by the solar panels and stored by batteries into AC power that you use in your home.
When I say it is a “want” and not necessarily a “need” I mean you can do without an inverter. But you will need to wire (or re-wire) your entire house for DC power and purchase special fixtures and appliances to utilize that DC power. This fact makes the Inverter a very practical.
Inverter can also perform other functions like grid inter-tie functions and back up generator management.
Which Inverter you choose depends on a number of factors:
- Quality or cleanness of the power needed
- The maximum continuous power you might use
- The way you choose to wire your system
- What additional functions you want to manage
- What you can afford to purchase
The Battery Bank: to store the sun.
A third item you may want in your home solar power system is a bank of Batteries. The purpose the Batteries is to provide storage for your excess electricity. This give you stored electricity to use when the sun and your system are not making electricity.
Batteries are only necessary if you choose or need to be completely autonomous, or “off-grid”. Alternately, you can also choose to connect your home solar power system to the electric grid. With a Grid Inter Tie System, as they are called, the extra power you make while the sun is shining is sent into the electric grid. When your system is not making power, your home uses electricity from the electric grid (managed by your electric company). With this set up, you still have an electric bill but it is off set, in theory, by the electricity your system makes and sells to the electric company.
Which and how many Batteries you purchase depends on:
- The longest estimated time you will not be able to make electricity
- The amount of electricity you would like to store
- How much maintenance you are willing to do
- The way you choose to wire your system
- What you can afford to purchase
Unlike other home solar power system equipment, Batteries have a relatively limited life. When well cared for, Batteries may last as long as 12 or 15 years. But you must plan to replace them. Rest assured, Batteries, even those used in your home solar power system, are 100% recyclable.
The Battery Charger: to manage the sun.
The fourth major item you will likely need for your home solar power system is a Battery Charger. The purpose of the Battery Charger is to manage the electricity going into your batteries. The Battery Charger regulates the rate of charge, amount of charge, and may keep track of additional statistics on your electric production.
As with the Batteries, the Battery Charger is only needed in an “off-grid” system.
The Battery Charger you choose depends on:
- The maximum amount of electricity your panels can produce
- The way you choose to wire your system
- What additional features you would like to have
- What you can afford to purchase
What other items do I need to build a home solar power system?
There are many more items you need for to build a home solar power system. These items may include:
- Lots of copper wire
- Conduit & associated electrical fittings
- Lightening protection
- Distribution box & circuit breakers
- Energy efficient appliances
- Low energy use lighting & fixtures
- Panel mounts and mounting hardware
- Battery box
- Equipment room
So I still want a home solar power system, where do I go from here?
It is definitely possible to design, install, and manage your own home power system. We did and still do.
Start by doing some research. And check back here often. We’ll cover in more detail in later posts how to estimate your power usage, select specific components, and configure your system. Even if you contract with an installer, the information we provide should help you better manage the design and installation of your own.
July 30th, 2009 at 4:34 pm
My family has been harvesting solar energy for centuries. Mostly it’s been by converting it into food, feed, and fiber, but some of it gets stored as cellulose for later use as heat.
Burning wood is carbon-neutral. Raising the trees pulls as more CO2 from the air then the later burning of the wood releases. The leaves, roots and mulch, etc., end up deteriorating over the years, and that CO2 goes back into the air as well.
But people look at trees as if they’re something special, and get upset when someone cuts down woods for pasture. Trees don’t do anything that other plants don’t do. An acre of sunlight is an acre of sunlight, whether the photosynthesis is performed by oaks and maples, by timothy and fescue, or ‘maters and broccoli. The only loss is when you have bare land exposed to the sunlight.
July 30th, 2009 at 4:49 pm
I agree with all you say, Harl! We like making our electricity too. It’s not really an “environmental” thing. Electricity is very handy and since we try and make much of our own stuff, why not power as well? And doesn’t CO2 help plants of all varieties grow? So how can it be a bad thing?
July 30th, 2009 at 7:00 pm
I like the panels on the tower. When I first saw the pic I thought they were being used as window shades, which is perhaps an idea with merit as long as the house has the correct orientation. Do you have more panels on the other side of the roof, or are you just very energy efficient?
July 31st, 2009 at 7:35 am
Hi Roger. We have panels on the top of the tower roof in the photo as well, another 4 panel array. We have talked about moving those front panels. They were mounted before the house was built.
Since taking that photo, we’ve added 4 additional panels to the roof of the house. We plan on adding another four in the future to power a house addition and chest freezer that now reside in another building.
August 3rd, 2009 at 9:52 pm
“And doesn’t CO2 help plants of all varieties grow?”
Isn’t Al Gore from Tennessee? Someone needs to “edumacate” him!
I’m in favor of clean air. I happen to *breathe* it. I’m not in favor of an open-ended experiment in seeing how foul we can make the atmosphere, and still survive. On the other hand, by the time you add together everything, including manufacturing, are solar panels really all that great ecologically?
My brother is working on a DOD pilot project to make jet fuel out of coal. The theory is that we don’t want foreign countries dictating whether we fly airplanes (or drive tanks, which use jet engines.) He believes, as I do, that a strong military should make peace more likely, if it wasn’t for the idiots in DC who want to take our spiffy new military toys out for a spin and show them off, so he is ambivalent about this. Still, one of the things that they’re looking at is how to do this as “cleanly” as possible.
We need to produce fewer lawyers and more engineers from our colleges. Back in engineering school in the 1970s, they told us that great breakthroughs in solar panels were coming in just a couple of years – and we haven’t seen them yet, because of lack of research.
August 4th, 2009 at 8:15 am
Shhhh. Don’t mention the Gore thing again. The entire eastern U.S. seems to be suffering from the Gore Effect. And we don’t want an unusually harsh Winter!
Everyone is in favor of clean air. Not every one loves their fellow man enough to keep their own clean. It’s all about being a good steward. Did I mention we’re not into the solar stuff for “ecological” reasons? It’s about independence. If a real electric car were available (and it looks like Nissan is working on one), we’d want one of those too. Then we no longer have to buy gasoline. Sort of like saving your own seed and growing your own food.
There’s an ethanol pilot project here in the county. They wouldn’t talk to hubby about a job….only wanted “ethanol experience”, as if engineering isn’t a set of hard scientific principles. Most companies (and our society at large…..that’s why everyone wants to be lawyer) no longer value engineers. That’s why salaries have collapsed. Over supply. It’s not a standing army that makes countries strong, it is their engineers.
If we had a true free market, there would be lots of inventors (with and without formal engineering degrees). We’d have many new and exciting technologies and plenty of financial incentives to develop them. Unfortunately, the government has taken over R & D via grants, direct research, overpriced and useless patents and regulatory barriers to the little guy. If he could, hubby would be running a pilot plant using sweet sorghum, not switch grass, and power it with waste pine, not natural gas or electricity from the grid. But he’s not a professor at a state/federal funded university.
October 4th, 2009 at 3:35 pm
I run a website about solar cookers and I am also interested in anything related to sun power and about ways to use solar power. I am working these days, even if a bit late, to add solar panels to my house so your article was just right.