What is solar energy?
Solar energy is energy from sunshine in the form of radiated heat and light. Solar energy technologies harness the sun's energy for practical ends. These technologies date from the time of the early Greeks, Native Americans and Chinese, who warmed their buildings by orienting, or positioning them toward the sun. Solar technologies provide heating, lighting, dry clothes and provide electricity. There are two distinctive categories: active and passive.
These diagrams show how solar energy works, simply.
How a solar cell works
click on image to enlarge
What type of funding is currently available for solar systems?
On July 9, 2008, Governor Rendell signed into law the Alternative Energy Investment Act which, among other things, will provides $100 million in grants for solar photovoltaic systems and solar water heating systems for homes and small businesses. The legislation also provides $80 million of support for larger solar installations and solar companies.
The residential and small business program is up and running! The residential program is currently in TIER TWO of three. Each tier lasts until 10MW of solar are installed through the program, and then rebate levels step down. Tier two offers $1.75/Watt rebates for projects up to 10kW (down from $2.25/Watt – time is of the essence if you are planning an installation!) For most customers this comes out to about 25% of installed cost.
The PA Sunshine small business rebate program rapidly moved to Tier 4, whose funds are also early exhausted. Tier 4 offers $.75/Watt up to 10kW and $.50/Watt and $.25/Watt as the system size increases, up to 200kW. We are optimistic however, and our contacts at DEP have noted that additional monies for the commercial Sunshine rebates should be available shortly.
SunPower is PA’s original solar company, one of about 10 in the state when the PA Sunshine Program opened last May. We were one of the first approved contractors for the PA Sunshine Program, which is managed by the PA DEP.
What are Solar Renewable Energy Credits (SRECs)?
The state of Pennsylvania, as well as many other states, requires electricity suppliers to provide a percentage of their electricity sales from solar generation – this requirement, stipulated through legislation, is called a Renewable Portfolio Standard. If the electricity suppliers and distributors do not meet their requirement, they must pay a penalty called an Alternative Compliance Payment.
This means that electricity suppliers/distributors will a) Have to construct large solar arrays to provide sustainable electricity or b) More likely, they will purchase this power in the form of “Credits” from homeowners and businesses that have solar installed on their homes and facilties. If you own solar photovoltaics, you produce SRECs, which can be sold on the open market like any commodity. Price per SREC varies and fluctuates with the market, and will continue to do so, but current pricing is approximately $300/SREC (you can visit www.srectrade.com for info. on current pricing and recent sales!) SunPower will take care of registering your system and aggregating your SRECs.
Can solar power be used to heat my home and business?
Solar water heating is very effective and affordable, capable of delivery up to 90% of a typical homes water heating needs throughout the year. Solar space heating is somewhat different. While no pre-engineered residential solar space heating systems are available on the market, solar energy professionals can engineers these systems for you. Solar space heating systems can heat well insulated houses with in-slab radiant mass floors reliably. Radiant floor space heating works well in new construction or renovation projects, but the draw back for existing homes is its affordability due to the other alterations that will need to be done in order for the installation to perform optimally. Other options for using solar to heat your home or business are increasing insulation and using Passive Solar technologies such as large, energy-efficient, south-facing windows.
Solar Radiant Floor Heating
How much solar electric power is needed for a typical home?
There is no simple answer to this question. Each home is different, and the amount of electricity you use is very dependent upon your lifestyle, your appliances and how your home was built. In addition to gauging the size of your system based on current electricity use, SunPower will work with you to reduce your electrical consumption in other ways.
How does a solar water-heating system work?
Every solar water-heating system features a solar collector that faces the sun to absorb the sun’s heat energy. This collector either heats water directly or heats a “working fluid” that is then used to heat the water. In Active solar water-heating systems, a pumping mechanism moves the heated water through the building. In Passive solar water-heating systems, the water moves by natural convection. In almost all cases, you will need a conventional electric or gas heating system as a supplement to the solar water-heating system.
Solar hot water system
Detailed diagram of solar hot water collector
What about heating my swimming pool with solar?
Solar pool heating is the most common way that people in the US today utilize solar energy. Solar pool heating systems increase water temperature by 10 degrees or more than an unheated pool, and can extend the swimming season by 2-3 months. Solar pool-heating systems work very intuitively, by using the sun to heat water in black tubes and then transferring the heated water through your pool’s filtration system. Solar pool-heating systems are also very cost-effective – your initial investment can usually be recovered in approximately 3 years or less.
How long will a solar system last?
Most solar panels have a 25 year power warranty from the manufacturer. This is longer than almost anything else you can buy and solar panels can outlast their warranties. The panels are durable and, while made of tempered glass, they are quite strong. Solar panels pass hail tests, and are regularly installed in Arctic and Antarctic conditions. The rest of the system components (batteries, wiring, etc.) are generally warrantied up to 5 years, but will vary. Inverters, another integral part of your system, can have warranties up to 10 years.
Due to the longevity of a solar system investment and the equipment warranties, it is critical to choose an established contractor that will a) Build your system to last! And b) Be around in 25 years to continue to service and support you, your system and its warranties.
How do I choose a solar installer?
- DEP list
- Trainings and certifications
- Years in business, experience
- Knowledgeable about the installation as well as the financing! Do they sub out the install or other parts of the job after they sell it to you?
Do I need to install a new roof before the solar panels are installed?
As solar panels will last over 25 years roofs do need to be in decent condition (it does not make sense to remove and reinstall the panels after only a few years.) However, after the panels are in place, they will greatly reduce the wear on the roof by blocking ultraviolet rays, keeping most snow and ice off the roof, and keeping anything from hitting the roof. Most installations do not require a new roof prior to PV installation, but SunPower will do a site survey to determine if a new roof is needed.
How much space does the system need? Do the panels need to be mounted on my roof?
The space required for a solar installation depends on the size of the system. A good rule of thumb is that for each 1 kW (kilowatt) (1000 Watts) of solar you will get 1000 kWh (kilowatt-hours) per year or approximately 84 kWh per month. A typical residential system (4.8kW) will require 24 200 watt panels, which will take up an area of approximately 450 square feet. SunPower will visit your home to do a site survey of your home or business in order to identify the available “solar window” on your roof. We can also look elsewhere on your property. The number of panels we can fit or install will determine the maximum size and therefore output of your system.
If I sell my property, what effect does PV have on the sale price?
Energy conservation and renewable generation adds value to a home. Surveys have shown that for every $1,000.00 saved per year, $20,000.00 is added to a home's value. Solar energy can be one of the best home improvement investments you make.