Finding ways to add alternative energy to an existing home can be a challenge. And a challenge worthy of our ProudGreenHome experts.
So we asked our Approved Contributing Experts, also known as ACE's, to tell us about the top challenges and solutions to adding alternative energy to a home.
Ted Clifton, founder of Zero-Energy Plans LLC, and CVH Inc.:
When adding alternative energy sources to a home, I often find the biggest challenge to be that the original design either had the ridge running north to south, instead of east to west, or the roof was so littered with dormers, plumbing vents and other obstructions that there is no place on the south face of the roof to install a solar hot water heater or photovoltaic (PV) panels.
The only solution to this is some kind of a ground-based system, like a rotating array on a pedestal, or mounting the system on a garage or garden shed. We have developed a whole series of what we call "Rooms with a Paycheck" to answer this need. These are small, fully self-contained living units, made to be installed in your backyard and covered with PV panels. They will not only power themselves, they will also provide much of the power needed for your house. Our 120-square-foot model is now available for viewing on our website.
The second challenge is somewhat related to the first, but more difficult to deal with. That is the issue of shading, either from trees, or from homes or buildings on other properties. My own home is in a very heavily forested area. Others in the neighborhood have removed a lot of their own forest, but I have chosen to keep mine. Until I take them down, my trees will eat up a lot of the carbon produced in generating the power my homes uses. Sometimes that is the best we can do, under the circumstances. Investing in a solar or wind power farm through your local utility company may be a good way to assure that you are using "green power" even though it needs to be generated off-site.
The third challenge is that of getting the power lines run from the solar panels to the most logical place for the inverter, and the connection to the main breaker panel of your home. Similar issues arise with the addition of solar hot water systems. In single-story homes, there is usually an attic in which lines and pipes can be run to access almost any room in the house. Two-story homes are the ones that typically present the problems, especially if the water heater and main electrical panel oar on the lower floor.
These challenges require individual solutions, as every house is different. Try thinking outside the box; for example, does the main water heater really need to be where it is? Could you place an auxiliary water heater for the PV system upstairs, and use a circulation loop to connect that one to the original water heater? Could a branch circuit panel be installed upstairs, that would use an existing circuit from an electric dryer, for example? The dryer could run off a circuit on the branch panel, the inverter would be placed nearby, and the PV power would be run into the branch panel. The limitation, of course, would be the ampacity of the existing circuit, but you would not have to add both loads; as long as the circuit is large enough to handle the maximum output of the PV system, it will handle the system and the dryer at the same time, because there would actually be less energy running through the circuit to the main panel below, any time the dryer is running while the PV system is cranking out power.
To summarize, if you can solve the first two problems, your local alternative energy professional should be able to solve the third.
Melissa Rappaport Schifman, principal at Resonance Companies
We installed a 3.6 kilowatt solar panel system on our roof in October 2010, and I wrote about the entire process on my blog (it was not an easy process – the title is called Solar Saga.) Since I went through the process, and I spent a few years in sales and marketing at a local solar installation company, I feel I have a pretty good grip on the challenges of adding solar energy to an existing home. (Please note: this is about solar electric, or photovoltaic panels, not solar thermal collectors that heat your hot water.)
Challenge #1 : Figuring out all of the rebates and incentives so you can understand your net cost. Since solar is an upfront investment that lowers a homeowner's electric bill, the solar investment decision is usually based upon a quick payback analysis. (As a University of Chicago-trained finance person, I actually do a discounted cash flow analysis, but payback is easier to calculate and simpler to understand.) That just means calculating the cost of the system (parts and labor), less the rebates. Then, calculate the amount you will save in electricity costs per year, and see how many years it will take to pay for itself. But how does anyone know what the rebates are? Is there one central place to go?
Solution: The best source for all of these credits is the online Database of State Incentives for Renewables and Efficiency. Right now, there is a 30 percent federal tax credit (with no cap) for installing solar on your home. That is a real credit — not just a deduction — to your tax bill, but you won't realize it until April. There are also various credits and incentives offered by both states and utilities, some with deadlines and some with specific requirements (like the installer has to be NABCEP certified). Many solar salespeople will present the total cost and let you know about all the local rebates, but it's best to check it yourself. We even found a neighborhood grant program for solar, which our installer never knew about!
Challenge #2: Deciding on the right-sized and type of system for your home. There are usually several constraints for how many solar panels you can put on your home: budget, roof size, roof orientation, shading, and the home's structural ability to hold the weight of the panels. Do you want batteries, or not? Do you want to pay more for micro-inverters, or not?
Solution: Get at least one solar site analysis performed by a reputable solar installer, and ask for a range of options — including the largest system that could be installed. That way you have comparison numbers for figuring out cost and the amount of energy that will be supplied. My personal opinion is that unless you are off the grid, you do not want batteries. By storing power, you lose some efficiency, and it's another component that requires maintenance and repair. I am also a huge fan of micro-inverters, because each panel can then perform optimally, as opposed to the entire array performing at the lowest-common denominator.
Challenge #3: Deciding on the right installer. (This is key for any home remodeling project!)
Solution: Get at least three bids, do your homework and get referrals. We had several bids, and the installer that got the business was the one that physically came over to our home and took precise measurements of the roof as well as the mechanical room, where the inverter might go. (I found it difficult to believe an installer's quote when he had not been in our home!) Make sure the company has had experience installing solar and will be around for a while, so if there are any issues, they will help.
Our particular experience in adding solar to our home was a little stressful due to the rebate deadlines and requirements, but many people are working on streamlining the process. In the meantime, good luck with being a pioneer, and congratulations to those who produce free energy from the sun!