Thursday, December 17, 2009

What to do about the grid?

There's only so much I can do about the grid in general. However, what am I to do about my relationship to it?

Twenty years ago I installed the first version of my solar electric system. At the time, I knew I wasn't going to be able to quite cut the cord from the grid. I'm surprised that all these years later I'm still connected.

Several things have held me back. The number one problem is winter. A month without sun can test anyone's faith in solar. There's a voltage meter in my kitchen that's connected to the battery bank. If the voltage drops lower than I like, I throw a switch and charge the batteries from the grid. In the winter that switch gets thrown way too much. At least my batteries have a full charge in case of a grid outage.

Here's what's running on the grid: The oil furnace. It never ran right on my old style modified sine wave inverter. It uses a fair amount of electricity (oil gun, blower motors, etc.) during a time when solar production is quite low. The answering machine. It's a constant low draw that's best not put on the inverter. I was given a big air compressor that requires 240 volts and my alternate energy system only puts out 120. Only use it a handful of times per year, but it's handy when I do. Some hot water heating -long story best handled in a post of its own. Some part of my laundry gets done on-grid. Some refrigeration. In the winter, when temperatures drop below zero, either the diesel truck or car gets their block heater plugged in. Otherwise the diesels just won't turn over.

The easiest thing in the world would be to replace the grid with a backup generator. That could happen, but only if I had the right generator at the right price. Right now it's possible to charge the household battery bank from my truck -'94 Ford F250 7.3 liter turbodiesel. The truck is wired up with a 2000 watt inverter. Since the truck has been converted to burn waste vegetable oil, it's cheap to run. It's possible to charge the house that way, and I'd probably do it in an emergency. For day to day use, however, it's seems like keeping a dragon chained to light your campfire.

For half the year, it'd be very easy to get by without the grid. The other half, we'd have to conserve, have another way of generating power, or some combination of the two.

As for the things that currently are exclusively on the grid, they could be handled. The oil furnace could be replaced with a propane heater that doesn't use electricity. If mounted in the basement, the plumbing wouldn't freeze if we weren't around to feed the woodstoves. The answering machine could be replaced with either a DC version, or a message service. The 240 volt air compressor could be traded for a 120 volt machine. Laundry could be done only on sunny days. We could downgrade to a smaller fridge. Wouldn't hurt to throw another solar panel or two on the array.

I've given some thought to adding a windmill. It's often windy when the sun doesn't shine. The price of windmills has come down. There are some problems with my location. The house is on the side of a good sized hill. Large hemlocks surround the place. A tower high enough to clear the turbulence caused by the hill and trees would cost a small fortune.

For about 7 years we temporarily solved the winter problem. We drained the plumbing, shut the house down, and traveled all winter. That works. I tied a canoe to the car and drove south until it stopped looking funny. Last winter, family obligations kept me north, and may do so again this winter.

In spite of the problems of doing so, I'm getting more and more tempted to pull the plug. The utility charges $35/month just for being hooked up. Imagine getting a $37 electric bill. That's $35 for the meter fee and just $2 for actual usage. It's over $400/year before I use a single watt. Nice system they have there.

Next summer I think I'll kill the main breaker and see how many months we can go without the grid. Who knows, maybe I'll have figured out something by fall.



  1. In 1999 I built a massive solar power system at my place. Seimens solar panels, hooked to a big bank of deep cycle batteries, which , with a big diesel generator, flowed into an inverter. It was text book.

    But, in winter there wasn't enough sun on my mountainside to charge the batteries.

    The batteries themselves were high maintenance, having to be run on an equalization cycle every week. They had a useful life of 3 years, cost a fortune, and were a bitch to replace. Getting rid of the old ones was a major evolution.

    It turned out, in the long run, that my generator was the best bet. Hooked into a transfer switch, when the power goes down (which is frequently here) I just throw the switch and run on the generator until the grid comes back on. Sometimes hours, sometimes days.

  2. I had good luck with Interstate golf cart batteries. Local dealers. Not too pricey. Got 7 years out of my fist batch -where I did every mistake in the book. Went 10 years with my second batch.

    I used to do an equalization charge once in the summer. Don't even have to do that with the new charge controller. Watered the batteries twice/year.

    When I do get a sunny day in the winter, my system generates power like crazy. The reflection off the snow really gives it a boost. Late winter/early spring produces well. November and December tend to be bad.

  3. It's about usage. I have not had to run the generator since mid summer as a matter of fact the generator is not even hooked up now.

    If you replace your oil heater with a propane one think about an old RV propane refrigerator. They don't use that much fuel and works fine.

    I do laundry at the laundromat if I can't hand wash it here.

    As far a grid attached power goes it is much much cheaper than a big solar power system any day. Although you are dependent on the power company and an income to pay the bill.

  4. I have 6x15 watt panels and with me being a o/o in trucking I have put my battery bank together with 3x12v truck batteries. I noticed on yesterdays blog you had your panels on display. What is the wattage of your system. I plan on gathering at least 6 more panels that would increase my panels to 180 watts minus 10% for degregation.

    I have the refridge / freezer from my truck which is a 36v unit in the house as a back up means and along with tv/vcr/dvd and the scanner I see how well we work with the 12v&120v appliances from 2000 watt power inverter and direct 12v hookup.

    I went to basspro and got a 12v w/breakers 6 unit power board. I plan to put the 12v perimeter lights and a few other things like water pump and what nots to it as I increase my power storing and generating capabilities.

    I have many solar power border lights as well as a solar power flood light for the Flag to be lighted at night. I am not trying to be "green" not that it is a bad thing for those to believe my purpose is to make sure I can cut off the grid once and for all and save my pocket from being raped anymore than what has been done or planned for "We the People" by those so caring public servants that represent the masses.

    I mainly wish to insure that my wife, and family members have a means to be safe without worrying when things get rough. Last year when Ike came through the Ohio valley my neck of the woods was without power for 6 days, but not us we had our panels providing lighting and power at night and the gas genny providing power in the day and also was aiding in the charging of the battery bank to make sure that we had power at night without keeping people awake. I was able to keep my business going with power for phones, faxes, internet and not miss a beat, all my contractors made pu/del and no one could tell there was a power problem for 7 states since we were up and running. None of my neighbors were ready even with a decent flash light, hell I had dual fuel lanterns, cook stoves, and hand crank dynamo products.

    I need to get more proficient at this off grid skills while nobody is noticing what I'm doing on our lil piece of land. And coming to sites like yours helps greatly to educate and inspire, keep up the good work. Feel free to email me and go over any ideas or suggestions you may have on getting better at starving the beast.

  5. Okay, a few things here. About the panels. The small ones are 48 watt at 12 volts. The large one is about 200 watts at 24 volts. The array used to run at 24 volts, but since I got an Outback charge controller, I rewired the system to 48 volts. It reduces line loss to the house. The charge controller reduces the incoming voltage of the array to the 24 volts of the battery bank.

    I had a Servel propane fridge for about 10 years. It lacked the quality of the old Servels and was junk at the end. I've got a small electric fridge that goes from off grid to on grid, depending on available power. By summer it should be just my wife and I here and we should be able to downsize to an even smaller one -and insulate the heck out of it.

    I'm quickly reaching the point where I'm willing to live on a lot less power so as to stop feeding the beast.

    This winter the basement has a much better woodstove and my basement is warmer. Warmer batteries hold more power, so I've stretched the number of sunless days I can go without charging from the grid.