Low-tech Magazine

How (not) to resolve the energy crisis

Increasing the share of renewable energy will not make us any less dependent on fossil fuels as long as total energy consumption keeps rising. Renewable energy sources do not replace coal, oil or gas plants, they only meet (part of) the growing demand. The solution is simple: set an absolute limit to total energy production. Why should we not be able to cope in 2030 with the amount of energy we consume today?

Wind powered factories: history (and future) of industrial windmills

In the 1930s and 1940s, decades after steam engines had made wind power obsolete, Dutch researchers obstinately kept improving the – already very sophisticated – traditional windmill. The results were spectacular, and there is no doubt that today an army of ecogeeks could improve them even further. Would it make sense to revive the industrial windmill and again convert kinetic energy directly into mechanical energy?

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.

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.

Carbon sequestration: bury the idea, not the CO2

Why introduce yet another expensive, energy-intensive and risky technology if there are so many other and better ways of fighting global warming? 

Capturing CO2 from the smokestacks of power stations with the intention of storing it in underground reservoirs, oceans, rocks, consumer products, chemicals or fuels has gained a lot of credibility recently. Many experts believe that we will burn the world's remaining fossil fuels anyway, and we should therefore try to lower the impact if we are to prevent a catastrophic climate change. Yet capturing, transporting and storing carbon dioxide raises energy consumption considerably and brings with it serious health and environmental problems. The benefits, on the other hand, are shadowed in doubt.

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?

The ugly side of solar panels

New research shows, albeit unintentional, that generating electricity with solar panels can also be a very bad idea. In some cases, producing electricity by solar panels releases more greenhouse gases than producing electricity by gas or even coal.

(Picture: Sungazer)

Wind up your laptop

The human body can deliver enough power to drive computers, television sets and washing machines – but it does go hand in hand with lots of sweat.

Eco-tech boffins dream of self-sufficient gadgets: mobile phones fed by solar energy, heartbeat-powered music players. However, the potential of these energy sources is much too small. Handles, cranks and biking machines on the other hand, do have a promise to be a powerful energy source. Swinging a crank for fifteen minutes is enough to power a mobile phone. Less than an hour of pedalling a bike can power larger machines. The only thing missing is a remedy for laziness.