Wednesday, August 12, 2009

System specs *Geek alert*


So The Husband was raised by and in a pack of engineers. Sometimes, I think it would have been easier to deal with him if it had been a pack of wolves. Communication with an extreme right brainer is what I imagine things were like for those around Helen Keller before the water pump break through. Here's what The Husband told his family about what we're doing in The Secret Cabin but be forewarned there's lots of "Geek Speak."

We plan to heat the cabin with 2 masonry heaters, one in the basement, and one on the main floor. They will be stacked on top of each other. Masonry heaters work by lighting a wood fire in the heater, which burns for about 1 1/2 hours. The fire burns very hot (no creosote due to the high temperatures). After the fire goes out, the heater continues to radiate heat for the next 24 hours or so because the large masonry mass which absorbed heat from the fire is gradually releasing it. In the downstairs heater, it will also have a water pipe going thru it, and that is how we will heat our water during 9 months out of the year. The remaining 3 months, we are either going to use solar hot water or the smallest electric on demand water heater we can find. Cellular service is almost nonexistent. If you stand in the loft and hold the cell phone to your head just right, you can get a signal. So the plan is to buy a cellular base station that I can hook an external antenna up to, and aim the antenna at the cell phone tower. It should work. For electricity, we are going to be off grid. I have a solar system sitting in the barn in Gibsonburg, just waiting to go up to Calumet. I have 8 Evergreen 205 watt panel, for a little over 1.6Kw worth of power. With the almost 2 hours worth of sun per day predicted up in Calumet during the winter (the worst time for sun), we should be producing about 3Kwh of power per day, or about 90Kwh per month. These panels will be attached to the top of an 8 inch pole. The electricity from the panels will be wired for about 90 volts DC and go to 2 Xantrex mppt charge controllers, which charge the batteries via outputting the best voltage and amperage for the batteries. This may change several times a minute, depending on clouds, time of day, etc. I have 12 Concorde AGM 2 volt batteries, that are about 950 amps apiece. Each battery weighs about 100 pounds, so the total battery bank is about 1200 pounds. The batteries will be wired for 24 volts. Theoretically, depending how much electricity Bheki uses, the batteries should last 3-6 days with no sunlight before they get down to about 50 percent charged. The more you discharge the batteries, the more you shorten the lifespan of the batteries. You really really try not to discharge the batteries below 50 percent. The batteries should last at least 8 years, hopefully closer to 15 before they need replacing. The solar panels should last at least 25 years, if not longer. So we have electricity sitting in the batteries. At this point, the battery output goes into a Xantrex 4024 inverter. This inverter puts out 4000 watts and 240 volts. The inverter output will be wired into a regular service panel (breaker box) in the house. At that point, all the wiring in the house is the same as any other house. It will run a submersible pump, lights, tv, computer, refrigerator, microwave, dishwasher, washing machine, and possibly, in the summer a very small electric heater (the smallest on demand point of use water heaters pull about 3500 watts, so they are close to the limits of the inverter). Do I expect to save money by being off grid and not using any propane or natural gas? No, I think it actually costs more to do things this way. We may never reach the point where we save more than we spent on the systems. But by the same token, you could say any money you spend on a car that has more than the bare necessities is not financially smart, yet I do it. I use a computer that costs more than comparable computers. I guess my philosophy is I vote with my money, and I am voting for this lifestyle. I didn't mean to get into philosophy, sorry. I spec'd out the system myself, and plan to install the system myself. I took an installers class at Owens a couple of years ago. It was very informative. If anybody is curious, the photovoltaic system cost about $20,000, minus a tax credit of about 6,000 for a total of $14,000 out of pocket. If you figure a 25 year lifespan on the system with 1 battery change, that would be about 680/year or 57 dollars a month, assuming the inverter or charge controllers do not need any maintenance.

Schew. As an additional note here to what The Husband's listed as expenses, the initial quote to bring electric back from the road was $8000. When all was said and done, it was expected that it would be higher than $8,000. Do I feel a panic attack coming on when I see the numbers? Yes. Would I do it this way all over again? Yes. Am I claiming that everyone can afford this? Hell no. It pinches, hurts, and leaves a little bruise. But, what if from the time I got my very first apartment, I had matched my electric bill and put it in my piggy bank? At least this way, FOR US, we're "walking OUR walk," we've paid our future electric bills in advance, we have physical property to show for it, and well, when the grid goes down, we don't.

No comments: