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Solar Energy In General

You should probably know where I’m coming from. My father was a city planner and was concerned about over population. Then I spent two years in the Peace Corps in India and got to see  many people with too little resources. I also got to see great recycling, in 1966. They had soda bottles that were used over and over, caps included. The folks there didn’t have a lot of “stuff” and when something broke, they fixed it rather than bought new. On returning to the US, we seemed to be wasteful, inefficient and taking more than our share (see the Story of Stuff). I’d love to see every twenty year old spend time in such a place.  I then worked in academic theatre for forty years. In the theatre you have a dream and a budget. The former is always bigger than the latter. Then there is the definition of academic, “the contemplation of that for which one does not have the money.” We had to get a lot of show for not much money.  Finally I must admit that I’m frugal, Scottish heritage and all that. So when it came to building a house I wanted the most recycled and energy efficient one I could build.

I installed a drain back solar hot water and then a photovoltaic (PV) battery back up system in 1984 when the house was built. I did it chiefly to save money and secondly because it seemed a good idea for the environment. Now these causes have been reversed. I have had grid tied PV installed on principle. I don’t plan to talk much about specific equipment here. Installers and web research (see links) to do that. As usual get at least three bids and let them know about each other. For a more complete information on my house please see Here, for Networx site and Energysage for more statistics on the house.

The Site
Can the sun get to your collectors? Tree growth and removal is an ongoing problem. Lets talk about trees and photovoltaic (PV) solar. In discussions on installing PV, trees are a frequent drawback. They are too beautiful around the house to remove. We should not clear cut land for PV. The other consideration is the roof of your house. It is best if you have a south facing roof with no encumbrances, such as chimneys and dormers. In New England, the best pitch for the roof is between 40 and 45°. At that angle, the snow will slide off the roof on the first sunny day. As the roof gets flatter, the snow will stay there longer, and the weight will be greater.

 What is the quality of your roof? How old are your shingles? It is best to have a newly replaced the roof with 40 year shingles. Taking solar panels off the roof, redoing the roof, and putting the panels back is expensive. Roofers don’t like it. The Installer will also need to check the roof strength for the weight of the panels.  The problem is that is that the panels weight is transferred to the roof by small legs at four foot intervals. The weight of the snow is not distributed over the whole roof. It is 10 – 20 point sources.

One day after storm, the snow has slipped off the panels. The panels on the left roof are still buried bacause the lower roof catches the snow.

Solar Hot Water
The first step is to conserve. Use low use shower heads, cold water for washing clothes, insulate your hot water pipes, use movable insulation on windows and so on. Please see Energy Saving. You can do some of these things yourself.

The value of solar hot water systems increases with the number of people in the house (quantity of hot water needed) and the further south you are. If you live by yourself in New England, solar hot water will take a long time to break even. It is not just a mater of installation cost vs. long term savings. Once the payback time is into decades, you need to consider the upkeep cost. The system needs periodic check ups on the propylene glycol and moving parts. Any service call from a quality installer can cost as much as a call from a plumber. The storage tank, like a traditional hot water heater, has a ten to fifteen year warranty. A new storage tank can cost $1500 installed. I found it wasn’t worth it. It is better to use the real estate on your roof for solar panels and get a heat pump, hot water heater powered by their electricity. An air to air heat pump hot water heater takes heat out of the air in your basement and puts it into the hot water tank. It has a back up electric heating element for quick recovery if hot water demand is high. I added one in 2014 and removed the hot water roof panels.The rebates can pay for much of the water heater.

Photovoltaic Systems
As with hot water do the easy things first: use CFL bulbs, put vampire loads on power strips with switches, etc. A generator tied to the furnace is handy in an ice storm. Grid tied PV installed before 2016 doesn’t provide power in a black out. It is best to own the system, as opposed to leasing or PPA.

I like PV because there are no transmission losses and it makes electricity during part of the peek hours so we may have to build fewer power plants. The PV panels last a long time. Grid tied systems need almost no maintenance and have no moving parts. Batteries are not long live, expensive and have several problems (as of 2023). Grid tied systems seem to be the way to go now that electric companies in MA have to go along with it. If you have a MUNI (municipal power company), they may not have any incentives. Contact them directly or see Munihelps. The state and federal tax rebates will help.  My one worry is the inverters. Inverters don’t have great warranties, only 10-15 years so they may need replacing thus raising the long term pay back.

NET METERING
When Net Metering is “one to one” or full-retail value net metering the credit for a kilowatt hour sent to the grid is the same as the cost of a kilowatt hour from the grid. One to one net metering allows the residential customer to store electricity from the summer as a credit on the electric bill for use in the winter when there is much less sunlight. During the winter heat pumps can use that electric credit to heat the house.

Some MUNIs (South Hadley in 2017) have dropped the Net Metering by two thirds. The obvious solution is for the homeowner to use as much electricity as possible when the sun is up: wash and dry clothes, use the dishwasher, use electric stoves, charge the car, run electric heating, use large power tools, etc. The side effect is that on hot summer days when power use hits a peek the residential solar home will be using as much power as possible. Literally making laundry, charging batteries, running AC, etc. (or hay) while the sun shines. So now the lower net metering will push solar owners to use electricity from the grid during the day (high grid load time) when they could be contributing electricity to the grid. In the future storage costs will drop. Solar PV will be installed with storage. Solar produces direct current (DC) and all batteries use direct current.  Low voltage DC lighting will grow. Eventually new homes with solar PV and storage may not even be connected to the grid.

Conclusion
Solar saves you money(see Financing PV). Much depends on energy costs and incentives.The costs will certainly go up. The inflation, reduction act and many state programs have greatly increased the incentives. I am retired. I put in solar and bought a Chavy Volt so that my energy costs will be fixed in the future.

More convincing is all we read about global warming, pollution causing health problems and the use of gas and oil for fuel. We will have to do something new in the future so we might as well get started. It is the right thing to do.

If you build a house, have a friend who is doing so, or even see a site being cleared, Please Please Please get them to orient the new house and roof to solar south. It’s a crime not to face the roof and a windows towards it. It is so easy to do before building and so impossible later.

PV systems vary greatly in their output. If there is snow on the panels they do not make electricity. If a panel has a square foot of shade on it the output drops to almost nothing. On a cold sunny day in the winter a 4 kw system meter may read just over 4,000 watts. On a cloudy day it may read 2,000 watts. In the summer a system in MA can produce three much electricity as in the winter. When the panels are hot in the summer, the output is reduced due to electronics not liking heat.

MY SYSTEMS

The battery back up system was 12 volt and ran many low voltage items (radio, lights, alarm system, screw guns, an attic fan and charging stations). It proved very useful in power outage situations along with a generator. Please note a grid tied system will not produce power during a power outage. All inverters shut down to protect the line crews. I prefer a back up generator to batteries. In 2030 batteries may be good enough and cheap enough to look at again.

The grid tied photovoltaic panels were installed during the summers of 2009 through 2017. I purchased most of systems from the Solar Greenfield Solar  and Northeast Solar in Hatfield. They were very good! The great thing about the system was the relatively new Emphase micro inverters. Instead of one large inverter in the basement, there is a small one under each panel. A shadow on one panel doesn’t turn off a whole string of panels and each panel reports what it is producing. The Enphase inverters let you monitor what each panel is doing in real time or for the past day or week. Take a look. I also chose Enphase because I did seven installs of 1-2 kw each and not one big install of 9.5 kw. That kept me from having to take out a loan and let me average out the price fluctuations. The down side of micro inverters is that when one dies you have to go up on the roof to fix it. If you have a large inverter in the basement, when it dies it is an easy replacement job.

The PV panels degrade at about 1/2 to 1 percent a year.

The Money Side

Most Electric companies in MA will pay you some percentage what they charge you for the electricity you send back to the grid. I should say that they will credit you bill for it. If you produce more than you use, you have a year to use the escess. If you don’t use it within one year, the credit is lost.

Electric companies do not want home owners to become power companies. Money to help you pay for PV installation comes from your town, state, electric company, and the federal government. Please note that every town and power company is different.The financing programs are changing all the time So you have to catch the best deal. It is rather like the stock market. A very good layout of what systems cost is available Here. If you live in South Hadley (a muni or municipal electric light co.), SHELD had a rebate program for a year.

PV systems usually have no maintenance, the panels last for 25-30 years and the modern inverters are conservatively guaranteed for 15-20 years. That said several of my 09 vintage inverters have had to be replaced. I am told that is no longer a problem.

There are several fairy tails about PV. Solar panels will not suck up all the sun so we have none left for crops. There is very little light reflected off the panels and what there is goes onto the roof or ground. Drive by the road facing array next to Atkins off Rt.116 to check this out. When headlights hit an array they will be reflected up into the sky. Not back at the driver! Most of the energy from the sunlight is used in the panel so there is very little chance of an array melting the siding off a house. PV panels in this area are cleaned by rain. They do not need to be washed. Some folk do not like the look of an array. I do because they may save the world. In a similar way I am not fond the look of electric wires on poles along the road. I accept the unsightliness because it is the only way to get electricity from the grid. PV is one of the only ways we have to get to have electricity without destroying the world due to climate change.

Please feel free to contact me for more information or a tour.

Photos of the Install History are Below.

  
  
  
  
  
 
 
 
 
 
 
 
 

 

The plywood safety rail at the roof's edge was a great help. The large panels in the background are the hot water system and the seven tiny panels are the 12v backup system.
The Enphase inverters are plug and play allowing easy inatallation.
PV panels went up the ladder.
INSTALLING ROOF SOLAR PV
Done! Grid tied Solar! Installs 1 & 2
2 large hot solar water on the left, 7 battery panels in center and grid tied on right
Install 3 being done by Solar Store of Greenfield 2012
Install 5 with old hot water & 12V battery PV systems removed in 2014
Last of the Roof Mounted PV
2kw Ground Mounted due to Ledge
Once a year look to be sure no wires are touching the shingles If they are then the wire's insulation will be "sanded" off