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.
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.
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.
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.
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.
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.
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?
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)
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.
Hand powered drilling tools and machines The drilling tools that appeared in the late 19th century were not only a vast improvement over earlier tools; they also have many advantages over their present-day successors, the power drills.
Pedal powered farms and factories Pedals and cranks could make an important contribution to running a post-carbon society that maintains many of the comforts of a modern life.
Firewood in the fuel tank Wood gas cars are a not-so-elegant but surprisingly efficient and ecological alternative to their petrol (gasoline) cousins, whilst their range is comparable to that of electric cars.
The Citroen 2CV: cleantech from the 1940s In spite of all the high-tech that has been squeezed into cars since then, the 2CV from 1949 is still more energy-efficient than the smallest model of the French car designer today.
Aerial ropeways: automatic cargo transport for a bargain These days, we use them almost exclusively to transport skiers and snowboarders up snow slopes, but before the 1940s, aerial ropeways were a common means of cargo transport.
The bright future of solar powered factories To power industrial processes like the making of chemicals, the smelting of metals or the production of microchips and solar panels, we need a renewable source of thermal energy.
Insulation: first the body, then the home Modern thermal underclothing offers the possibility to turn the thermostat much lower without sacrificing comfort or sex appeal.
The monster footprint of digital technology The embodied energy of the memory chip alone already exceeds the energy consumption of a laptop during its life expectancy of 3 years
The age of speed: how to reduce global fuel consumption by 75 percent Engineers treat velocity as a non-variable, while in fact it is the most powerful factor to save a really huge amount of energy - with just one stroke, at minimal cost, and without the need for new technology.
Ropes and Knots Ropes and knots are among the most ancient and useful technologies ever developed by man, predating the wheel, the axe and probably also the use of fire.
Email in the 18th century: the optical telegraph More than 200 years ago it was already possible to send messages throughout Europe and America at the speed of an aeroplane – wireless and without need for electricity.
Trolley canal boats For many centuries, canal boats were propelled by men, horses or mules on the towpath beside the water. Before diesel power took over, engineers developed several interesting methods powered by electricity: trolleyboats, floating funiculars and electric mules.
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