Low-tech Magazine

Small windmills put to the test

A real-world test performed by the Dutch province of Zeeland (a very windy place) confirms our earlier analysis that small windmills are a fundamentally flawed technology (test results here, pdf in Dutch). Twelve of these much hyped machines were placed in a row on an open plain (picture above). Their energy yield was measured over a period of one year (April 1, 2008 - March 31, 2009), the average wind velocity during these 12 months was 3.8 meters per second (note: update on the wind speed). Three windmills broke. Find the disappointing results of the others below.

Who killed the electric grid? Fast-charging electric cars

Charging electric cars with off-peak power is a fantasy.

Fast recharging times generate lots of excitement, but what seems to be forgotten is that they can lead to a fabulous amount of peak demand.

If you charge an electric car with a battery capacity of 25 kWh during 8 hours, it needs a power output of 3,125 watts. If you charge the same car in just 10 minutes, it needs a power output of 155,000 watts.

Viva Las Vegas: LEDs and the energy efficiency paradox

The incandescent light bulb is abused by environmentalists – but the alternative will only raise energy consumption. More and more, compact fluorescent lamps are considered to be an interim technology, awaiting the arrival of Light Emitting Diodes (LEDs) and Organic Light Emitting Diodes (OLEDs).

At the moment, LED technology is no competition for the incandescent light bulb. However, it can be considered a worthy improvement of another technology: neon lights. Whether or not white LEDs will finally arrive, the success of coloured LEDs is a fact. Though some of them are definitely useful, they all introduce lighting in places and situations where there was no lighting before.

Urban windmills harm the environment

A small windmill on your roof or in the garden is an attractive idea. Unfortunately, micro wind turbines deliver hardly enough energy to power a light bulb. Their financial payback time is much longer than their life expectancy and in urban areas they will not even deliver as much energy as was needed to produce them. Sad, but true.

Life without airplanes: from London to New York in 3 days and 12 hours

Rising fuel prices are slowly killing airline companies. Can ocean liners save long distance travel and tourism?

Flying has become cheaper than taking a train or driving a car. Yet, environmental concerns, dwindling fuel reserves and fast rising kerosene prices are threatening to turn airline travel into a privilege for the rich again. This should not mean the end of mass travel or tourism, however. Before mass air travel took off in the 1960s, people crossed the globe in majestic passenger ships. Reintroducing ocean liners would be more than a nostalgic move: it could be a much more energy efficient (yet slower) way to travel.

Bring back the horses

Replacing tractors with real horse power could be the revolution that agriculture needs.

Horses and other draft and pack animals revolutionized transportation, war, hunting, manufacturing and agriculture. Work horses formed the backbone of industrial society until the first decennia of the 20th century, mining coal, ploughing fields and transporting goods and people in fast growing cities.

Reintroducing horses in city traffic would be a bad idea - cars might be noisy, dangerous and polluting, but mounts are even worse. In agriculture, however, animal power would bring surprisingly large environmental profits.

Leave the algae alone

While the first generation of biofuels is wreaking havoc on the environment and the food markets, the second generation is set to make things even worse.

Since it has become clear that ethanol and biodiesel made from food crops are doing more harm than good, the hope for finding a substitute for oil has shifted to algae and cellulose. If we can believe the advocates of this ‘second generation’ of biofuels, these combustibles will deliver way more energy than it takes to make them, without threatening the world’s food and water supplies. Upon taking a closer look, however, this is very hard to believe. They might even cause bigger problems than biofuels made from food crops. Maybe this time around we could sort this out before the damage gets done?

Why bottled water is good for the environment

Drinking bottled water is a much more ecological choice than consuming soft drinks, coffee, fruit juice or beer. Water drinkers should be praised instead of criticized.

Bottled water is under attack from environmentalists who preach that tap water has a similar quality and saves a lot of energy since it does not need to be transported by trucks. That might be true, but bottled water is not our biggest problem when it comes to drinking habits.

All other beverages consume huge amounts of water and energy during their production processes, which makes their ecological impact far more detrimental than that of bottled water. Like bottled water, most of them are distributed in bottles and cans, too. (Illustration: plan59)