Don’t Heat your Room with Tea Candles

November 19, 2014 by kris de decker Filed Under: Heating appliances, Random

hoax te candle heater

Friends and readers keep sending me links to a “low-tech” heating system in which tea candles heat a combination of ceramic flower pots. It seems you all need a course in thermodynamics, so let’s start with some basics:

1. First law of thermodynamics: you can’t create energy out of nothing, (and you can’t destroy it). This means that placing two ceramic pots on top of four candles does not increase heat production. You get the same amount of heat if you burn four candles without the pots.

2. Now imagine heating your room with four tea candles.

3. Get more tea candles. One tea candle can produce around 30 watts of heat, which means that you need at least 20 to 30 tea candles to heat a very small room (and replace them every 3 to 4 hours).

4. You have now built a small fireplace using tea candles. However, it isn’t running on wood but on petroleum — the stuff paraffin is usually made of. And above all,  you have built a fireplace without a chimney. Chimneyless fireplaces are very efficient, but they’re not so healthy and that’s exactly why the chimney was invented. Connecting your tea candle fireplace to a chimney will solve the indoor air pollution issue, but unfortunately 85-90% of the heat will then escape through the chimney. So you need more candles.

5. Forget tea candles, get some thermal underwear.

Pedal Powered Farming

November 15, 2014 by kris de decker Filed Under: Farming, Pedal power, Pedal powered machines, Random

culticycle pedal powered tractor

The Culticycle is a pedal powered tractor that can cultivate, seed, spray, or pull gear for most low horsepower tasks. We talked about the first prototype almost two years ago. A new version has now been released, built around a modular tractor frame. Tim Cooke explains us how it’s built and how it works:  [Read more…]

The Fuel Multinationals Run On

November 10, 2014 by kris de decker Filed Under: Consumption

“The western world now obeys the precepts of commerce. A bloody demanding religion, if you ask me. The do’s and don’ts change every season and your ‘everyone’ doesn’t want to be left out, so they rush headlong to comply. That continuous change has a function, a single aim. Maximum consumption. They want to go on milking you. From the cradle to the grave. Face it: You’re a brain washed, walking purse, a robot, the fuel multinationals run on.”

Esther Verhoef, Close-up (2009 novel), quoted by Culture Change: Consumption Civilization: our prospects since western civilization’s historical adaptation, 2014

Different Types of Windmill Sails

November 1, 2014 by kris de decker Filed Under: Random, Wind Power, Windmills

different types of windmill sails compressed 700 pixels

François Porcher has translated our 2009 article “Wind Powered Factories: History (and Future) of Industrial Windmills” (“Des fabriques mues par le vent: histoire (et avenir) des moulins à vent“) and sends us the image above to complement the illustrations. For a high-resolution image, go here. More articles have been translated to French and other languages.

Previously:

Building Dry Stack Stone Walls

October 30, 2014 by kris de decker Filed Under: DIY, Random, Walls

dry stack stone wall finished 3

You might take them for granted when you see one, but building dry stack stone walls is not for sissies: [Read more…]

Change Ringing

October 23, 2014 by kris de decker Filed Under: History, Mathematics, Musical Instruments

Despite the curtailing of their liturgical uses, at the beginning of the seventeenth century a lot of church bells remained hanging in church towers. Ringing them was an activity pursued with great enthusiasm, often by groups of boozy young men. Paul Hentzner, a German lawyer who traveled through England in the final years of the sixteenth century, wrote that the English were “vastly fond of great noises that fill the ear, such as the firing of cannon, drums, and the ringing of bells, so that it is common for a number of them, that have got a glass in their heads, to go up into some belfry, and ring the bells for hours together for the sake of exercise.”

It was in these long, beer-fuelled ringing sessions that change ringing was invented, as a codification of the disorganized ringing that Hentzner describes. It seems to have started in London and southeast England in the early seventeenth century; it spread, and by the 1660s was a fashionable recreation, with societies springing up all over south, central, and eastern England to further the practice.

St Mary-le-Tower Bellringers

[Read more…]