A couple of issues ago I described how I built a root cellar last year, with a curved, concrete arch. As of May, I’m pleased to report that the apples & vegetables kept well. I’m enjoying the tail-end of a 50-lb bag of potatoes that cost me $5 in October. I only had to discard a few apples where a bruise caused them to spoil. The apples are not as crisp as last fall, but they are edible, and will taste mighty fine when the system collapses and that’s all there is to eat.
So naturally I had to monitor the temperature throughout the winter, to make sure that it did not fall below freezing and spoil all the food.
At first I bought a few electronic thermometers with high/low memory. There were a few nights went the thermometers showed that the temperature had fallen below freezing at some point, even though the produce was still OK.
The root cellar is located below ground level, and it receives the heat that is naturally generated by the earth. It must be ventilated to prevent the buildup of mold, so the flow of air will cool things down when it gets cold outside.
So I needed to know when the temperature had fallen below 0°C, and for how long.
I looked for temperature recorders on the Internet. Industrial units can run close to $1,000, above my budget. I found a place that sold do-it-yourself kits ($50) which plug into your computer’s serial port. I ordered one, along with four probes. I soldered and assembled it, and it seemed to work. I wrote a program that displays a nice colour graph of the temperature over the past couple of days.
I ran some wire in the root cellar, and positioned three probes near the ceiling, centre and floor respectively, as well as an outdoor probe. I had to use an old 150 MHz laptop for data collection, as the new laptops no longer offer a serial port.
I had a lot of fun over the next few weeks, running out to the root cellar every morning to check on the previous night’s temperature curve. I was able to hold the temperature at a nice 1°to 2°C, with the floor occasionally dipping below freezing. It was clear how the inside temp. would dip when it got to –20° outside.
I bought an industrial thermostat on the Internet. I installed a 1000–watt floor heater inside the root cellar, with the thermostat set to hover above 0°C. I was able to fine-tune the setting by observing the temperature curve. To keep track of my energy consumption, I installed an old 110 V. electrical meter, and jotted down the kWh reading everyday. The whole place looked more like a laboratory than a rustic food stash.
I drew the line at running a 200’ LAN cable to the kitchen so I could get real-time updates.
I figure I used about 4¢ of electricity per day, which isn’t too bad. In the old days, they would place a burning kerosene lantern in the root cellar to keep things above freezing.
The probe circuit stopped working after a month or two, which was disappointing. I can’t figure out how to fix it. Oh well.
The issue of food sovereignty is very much in the news. As I expected, the rising cost of petroleum is impacting food production in many ways: fertilizer, pesticide, and transportation. It has become ever more important to be self-sufficient in food production.
Watch out for what’s happening in Egypt, which receives $2B a year in food subsidies from the U.S. There is a lot of unrest and poverty in Egypt. If things get bad enough, starvation could precipitate a revolt, which could spread to its neighbour Saudi Arabia, topple the monarchy, install radical clergy in government, and cut off the West’s oil.
We are six billion humans on a planet best suited for two billion. Anyone can see this will not end well. The Four Horsemen of the Apocalypse are retroactive birth control, just Nature’s way of saying “OK you f***ers, everybody out of the pool!”.