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.

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.

Is ecotech the new asbestos?

What will remain of greentech, cleantech and ecotech if nanotechnology turns out to be harmful for humans and the environment?

It’s hard to keep track of the soon-to-be-implemented technological solutions that will solve our energy and environmental woes by means of nanotechnology – the science of manipulating individual atoms. Solar panels and batteries might be far from optimal solutions now, but nanomaterials will boost their efficiency and dramatically lower their costs. Transporting electricity from solar plants in deserts may not be possible yet, but nanotechnology will bring us cheap superconducting cables and efficient hydrogen storage. Unfortunately, more and more research indicates that nanomaterials might become a severe health problem and an environmental nightmare.

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)

Why the electric car has no (wireless) future

The electric car is not a technology of the future, but from the past.

The electric car is 170 years old. This may sound surprising, but e-cars predate automobiles with a combustion engine. They were driven out of the market in the beginning of the 20th century because petrol engines had significantly better mileage. One century later, the electric car still faces the same – fundamental – problems. Furthermore, the need for batteries makes them eco-unfriendly by nature. The only possible green future for electric cars is a wired future: hooked up to the overhead lines, like trolleybuses and bumper cars.