Q: How does Solar PV work?
A: Simply, sun strikes the cells made of silicon a semiconductor and knocks electrons loose from their atoms, which flow through the material to produce electricity. This DC electricity is then converted to AC electricity through the Inverter.
Q: Can I use PV for backup power when the grid goes down?
A. No, not practically. The Inverter shuts down when power is lost so that it doesn’t back feed the grid. The Solar Array's output fluctuates so much that you can’t power anything. The only way to do it is by using the Solar Array to charge batteries so that there is a steady power supply to pull from. Batteries are still very expensive and right now, it is more cost effective to use a generator.
Q: What’s the Warranty on the panels?
A: The Average Warranty for the Solar Panels is 25 years. The Warranty states that it will produce at least 80% of its rated power for 25 years and historically they have produced electricity for 30 or 40 years
Q: What is the Warranty on the Inverter's?
A: Solar Edge Central Inverter's have a warranty of 12 Years. Enphase Microinverter's have a warranty of 25 Years.
Q: Is there a lot of paperwork?
A: Yes - but we will help you with all of it.
Q: How much do the panels weigh?
A: 300 Watt Panel weighs about 45 pounds.
Q: What are the dimensions of a panel?
A: A 300 watt panel is 36 – 40” wide and about 60-65” tall.
Q: How long does it take to get the State Rebate?
A: About 4 to 6 weeks after the Power Company sets the net meter.
Q: Is there any maintenance to the panels?
A: Not much. There are no moving parts so other than some occasional cleaning – maybe some snow Removal on low slope roofs - there is no maintenance.
Q. Which way does the Array have to face for the best solar gain?
A.This is called Azimuth and its 195 Mag degrees South = True South in New Hampshire. This degree changes depending on where you are in the world.
Q. What is Azimuth?
A. It is the orientation your house faces. On a compass reading, it is 195 degrees magnetic south due to the magnetic pull of the earth - that reading is 15 degrees off to the West, as True South which is 180 degrees. You must be careful when talking to someone if they are talking True South 180 degrees or Magnetic South 195 degrees, where they are same orientation.
Q. What is an acceptable amount of sun/shade?
A. 80% sun (20% shade) is generally the lowest level you want. A PV system will work at lower levels but, obviously with a lower output. You want good Sun from 9:00 AM to 3 PM all year.
Q. What are REC credits?
A. Renewable Energy Credits (REC's) are created from every Megawatt Hour of Electricity produced by a Solar Array. Electricity Suppliers must buy REC's in order to meet the New Hampshire and Massachusetts RPS Requirements. There is no ceiling or floor to the pricing of REC’s – it is a demand and supply market where the demand is set by the State and the price is set by the market. REC’s are political and they may not be around forever.
Q. Do I get a new Meter?
A. Yes. Your present meter will be replaced (at no charge) with a Net Meter which will have the ability to go forwards or backwards depending if you are making more power than you are using.
Q. How much is the Federal Tax Credit?
A. There is a 30% Federal Tax credit for both Residential and Commercial Installations. This is 30% of the Total Cost of the Solar Installation and it is good through 2019! In 2020 the Federal Tax Credit amount will step down.
- The Federal Tax Credit can be extended over a few years if your Tax Liability ins't as high as 30% of the cost of the job.
- If the Property is or will be a Rental Property, you may not b eligible for the Federal Tax Credit.
- There are many interpretations on how to apply the Tax Credit. Please consult your Tax Adviser!
Q. Is there a State Rebate?
A. The State is accepting Applications for Residential and Commercial Solar Installations. Rebates are Taxable and Solar Expansions are not eligible for the Rebate.
- Commercial Installations: There is a Wait List of Applications due to the State having limited Funding - the Rebate amount is not a guarantee. The Rebate amount is capped at $50,000.
- Residential Installations: The Maximum Rebate amount is $1,000. Depending on the State's Funding the amount is subject the change.
Q. Should I use Solar Thermal to heat my hot water or PV?
A. Solar hot water is more efficient and costs less but depending on the application and different rebates, PV may make more sense. Solar hot water will heat about 60-75% because you can’t size it large enough for the winter because it will be over sized for the summer unless you have a place to put excess heat in the summer (pool). Also you need to use the hot water within a day or 2 when you produce it or you loss it to heat loss. PV on the other hand, can produce 100% of your hot water, and all power produced is accounted for through net metering and use. The best scenario is using a hot water heat pump which is 240% +/- efficient in conjunction with an electric hot water tank. Now you only need 1/3 - ½ as much PV to offset the domestic hot water and you have 100% of the energy needed. The cost of the smaller PV system and heat pump will be comparable to the solar hot water which only does maybe 60- 75% of your hot water.
Q. What is meant by the efficiency of solar panels?
A. The efficiency is based on how a panel can convert the thermal solar energy to electricity based on a square meter of PV.
Q. Which is more cost effective – a Roof Mounted Array or a Ground Mounted Array?
A. A Roof Mount Array generally costs less because we don’t have to build a structure to mount the panels on. However, a Pole Mount or Ground Mount Array will usually produce more energy because the Array can be located in a location with less shade and at the perfect Azimuth for the best production. So eventually the pole or ground mount will become more cost effective after it is paid for itself.
Q. What about snow on your panels?
A. Depending on the roof pitch will determine how the snow slides off the panels. At 40-45 degrees, (10- 12 pitch) it generally slides off on its own. For 30-40 degrees (7-9 pitch), this will require a little snow maintenance. Light fluffy snow will be off the next day, where freezing rain/snow will freeze to panels and might be several days before it slides off. Roof pitches flatter than that will have snow on panels for days and maybe weeks if not helped along with a soft roof rake.