So, you’re a weekend cottager without electricity, and your garden dies during weekdays for lack of watering. And there are times you’d prefer a warm shower to jumping in a cold lake. There are videos you’d like to watch in the evening. And you’d like some way to keep the milk, eggs, and beer cold. Maybe even a ceiling fan for those hot, hot nights.
Have you thought about checking out solar energy?
To give an idea of the possibilities, I spent a morning with Chuck Gobeil, a friend in Kingston who runs Renewable Energy of Plum Hollow Inc. If you look in the Yellow Pages for your area under « solar energy,’’ you’ll probably find a similar store.
We began with the presumption that you’d like to start small. To generate the electricity you’ll need, Gobeil suggested a $1,000 starter kit containing a 50-watt photovoltaic panel and mounting rack (available in varying shapes, and a bit more than a third of a square metre in size) to erect where it will receive constant, direct sunlight; two deep-cycle marine batteries, which are about the size of car batteries; a regulator to keep the batteries from overcharging; and a battery gauge to indicate the condition of the batteries.
The batteries will deliver 2,000 watt/hours of electricity — in other words, they could run something drawing 20 watts for 100 hours. And the photovoltaic panel, generating all week long, can replenish the batteries with about 1,250 watt/hours of electricity.
This replenishment rate means you have to choose a combination of equipment that draws no more than 1,250 watt/hours of electricity over the weekend. Otherwise you’ll use more than your photovoltaic panel can generate, and the batteries will gradually run down.
Here’s what we came up with, and the amount of use it would get:
• Three 15-watt compact fluorescent light fixtures ($60 each). Each will produce the same amount of light as a 60-watt incandescent light bulb. (10 hours or 450 watt/hours)
• A small TV-VCR which uses 100 watts per hour. (four hours or 400 watt/hours)
• Water pump and pressure tank for bringing lake water into the cottage for dishes and washing ($300-$400). The pump will use 100 watts per hour. (one hour or 100 watt/hours)
• A soaker garden hose, which drips water along its length instead of spraying it from the end, to water flowers and vegetables while you are away. It can be run by the pump and pressure tank, but you’ll need to add timing equipment that will control when it runs, and for how long ($350). (2 hours or 200 watt/hours)
• A swimming pool solar collector for your roof to heat hot water ($250). It’s a black plastic mat, about 1.2 metres wide by 3 metres long, containing dozens of tiny channels for water. As the water passes through the channels, it’s heated by the sun. By the end of the day, it can reach 38° Celsius. You’ll need a small, 10-watt pump to continuously circulate water through the collector ($250), and the warmed water can be stored in a discarded, insulated, electric hot water tank. (one hour or 100 watt/hours)
At this point, you’ve reached the maximum electricity use that the photovoltaic panel can replenish. If you want to add something more, say a ceiling fan ($250-$300), which could use 400 watt/hours on weekend nights, you’ll have to substitute a larger, 75-watt photovoltaic panel ($750 instead of $500).
For keeping your milk, eggs, and beer cold, you can buy a kit for converting an old, disused refrigerator ($1,500). You’ll end up with a super-insulated cold box whose refrigerating motor and compressor can be powered by the two existing 12-volt batteries. However, it will draw 400 watt/hours a day (800 watt/hours for a weekend), and you’ll need two 50-watt photovoltaic panels, instead of one to keep everything running. For week-long use, you’d need two more panels and two more batteries.
My favourite, in all of this, is the scheme for watering the garden. I’d love to have fresh broccoli and pine-nut salad, at sunset, down by the lake.