Solar

Solar Energy is the light and head that comes from the sun. It can be harnessed to provide energy in several ways:

• Photovoltaic cells- Convert sunlight directly into electricity. Solar panels are made up of groups of photovoltaic cells.

• Solar thermal technology- Makes hot water or steam from concentrated sunlight.

• Passive solar heating- Where buildings are designed or remodeled to take advantage of the sun’s heat in the winter and eliminate the effects of heat transfer “shielding” to living spaces in the summer.

• Planning a PV System- Photovoltaic (PV) Solar Systems convert sunlight directly to electricity.  They work whenever the sun is shining and work best when the sunlight is more intense and the solar panels are placed so that they get maximum sun exposure. They are a zero-emission renewable energy source and allow consumers to make electricity without pollution.

• Solar Panels- Made up of photovoltaic (PV) cells that convert sunlight into direct current (DC) power, and are usually installed on the roof.

• Inverter- To convert DC power into the alternating current (AC) power that is typically used to power your home.

• Electrical Panel- (breaker box) to receive the AC power from the inverter.

• Utility Meter- To continually measure your electrical supply.

• Balance of System- (BOS), the support structure for solar panels, wiring etc. Note that BOS and labor for installation can be a costly component of a PV system.

 

1. Determine if you have enough sun for solar.
For a solar panel to work at its optimal level it needs clear and unobstructed access to the sun’s rays for most of the day throughout the year.  Panels oriented to the south get maximum exposure. Panels are generally placed on rooftops. If the roof does not have the proper orientation, enough space, or is shaded by trees or other structures, panels can be placed on the ground. Some creative installations mount panels to create covered parking or provide shade as window awnings.

Determine what portion of your energy needs you want a PV system to meet. Start by figuring out how much electricity you currently use.  Add up the kilowatt-hours (kWh) of electricity use for the previous year. Record the actual kWh used and don’t multiply one month’s usage by 12 because usage can vary widely over the course of the year. Note: If you do not have your electricity billing statements, your utility company should be able to supply kWh information.

The total number of solar kWh necessary to generate for a year determines the number of solar panels needed.

A chart on page 7 of the Solar Consumer Guide published by the U.S. Department of Energy estimates the number of square feet needed for different-sized systems. 

3. Determine if the roof can accommodate the system.

PV solar panels can be installed on any type of roof, but roofs with composition shingles are the easiest and those with slate the hardest. If the roof needs to be replaced in the near future, it can be cost-effective to do it before the PV installation to avoid the extra cost of removing and reinstalling the panels when the roof is redone.  Another option becoming cost competitive is to buy solar shingles that serve the dual purpose of solar panels and roofing shingles in one product. Click here to read more about solar shingles.

4. Choose between a stand-alone system and system connected to the electricity grid. 
If you are connected to the grid, the power produced by your solar panels is fed back into the grid and the electric company supplies you with your power. This is called net metering. The electric company keeps track of how much electricity you generate and how much you use. If you use less than what you generate, the energy company will generally give you a credit.  The Database of State Incentives for Renewables and Efficiency (DSIRE) explains the rules on net metering, including how much you are paid for generating excess power. If you use more than what you generate, the utility charges you for the excess. Grid connected systems have the advantage of more efficient utilization because there is no storage loss. However, if there is a power outage, you are out, too.

If you have a stand-alone system, you only have access to the energy that you produce. Because solar panels only create electricity when the sun is out, you must install batteries to use energy when the sun doesn’t shine. However, if the grid goes out, your power stays on as long as your batteries stay charged.

You can also install a battery system to provide backup in systems connected to the grid. When the grid system is functioning properly your home will use the power generated from your solar panels or pull electricity from the grid. In the event of a grid blackout the system can switch to “off-grid mode” allowing your home to be powered by your batteries, and your batteries to be recharged by your solar panels.

5. Understand your financing options.  

The three most commons ways to finance solar in your home are:

Direct Purchase – Buying the system outright is the simplest and most financially beneficial way to get solar because the buyer can take advantage of federal, state and local incentives, which can amount to up to 30 percent of the purchase price. Check the U.S. Department of Energy’s DSIRE – Database of State Incentives for Renewables and Efficiency database to find out the current rebates and incentives in your area. The best way to finance a PV system for your home is through a mortgage loan. You may also be eligible for the pilot PowerSaver Loan Program that allows homeowners to borrow up to $25,000 for terms as long as 20 years to make energy improvements in their home.

Power Purchase Agreement (PPA) – PPA is a zero-down financing option. The solar system is owned, operated, and maintained by the supplier and financing partners. The advantages are that the buyer does not need to put any money down, and the solar electricity is sold to the buyer at a discounted, locked rate (the PPA price). The downside is that the supplier, not the purchaser, receives any available rebates & incentives.

Solar Lease - Like a PPA, a solar lease does not require that the buyer put any money down, but unlike a PPA the solar electricity is NOT sold at a discounted, locked rate. Lease terms are generally for around 20 years, but some leases can be shorter. In most leases the purchaser has the option to buy the system at any time during the lease or at the end of the lease. The purchase price is usually predefined in the lease contract. This works well for people who prefer to make payments over a longer term rather than make an up-front investment in solar. However, like a PPA the purchaser can NOT take advantage of any available rebates and incentives. When you sell your home you can usually assign a solar lease to the purchaser if they have the proper credit.

Your quote for a PV system should clearly state the maximum generating capacity of the system and an estimate of the amount of energy the system will produce each year. Ask an installer to quote your price both for direct purchase and a solar lease or PPA so that you are sure that the lease or PPA prices are not based on a higher total cost.

While it’s possible to install a system yourself, there are many advantages to hiring trained professionals.

Participate in a solarize campaign in your community and choose from carefully selected eligible installers. 

Look for a solar (PV) installer.