Low-tech Magazine

Insulation: first the body, then the home

You could fill a library with reports and books describing the importance of energy-efficient heating systems and home insulation. However, not a word has been said or written about the energy savings potential of clothing, even though there has been a lot of progress in this area too. Modern thermal underclothing offers the possibility to turn the thermostat much lower without sacrificing comfort or sex appeal. The potential energy savings are huge; the costs are almost nil.

This article explains through science and statistics how to maintain thermal comfort at any given indoor temperature using only clothes.

The velomobile: high-tech bike or low-tech car?

Recumbent bikes with bodywork evoke a curious effect. They look as fast as a racing car or a jet fighter, but of course, they're not.

Nevertheless, thanks to the recumbent position, the minimal weight and the outstanding aerodynamics, pedalling a "velomobile" requires three to four times less energy than pedalling a normal bicycle.

This higher energy efficiency can be converted felt in terms of comfort, but can also be utilised to attain higher speeds and longer distances - regular cyclists can easily maintain a cruising speed of 40 km/h (25 mph) or more. The velomobile thus becomes an excellent alternative to the automobile for medium distances, especially in bad weather.

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. Many of these ecological solutions could be applied today instead of diesel engines. Because of the very low energy requirements, they could easily be powered by renewable energy, generated on the spot by water turbines located at sluices. One trolleyboat line is still in use.

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. 

Water powered cable trains

Cable trains (or funiculars) are one of the most energy-efficient modes of transport out there.

A large portion of the power required to pull up the ascending car is delivered by the counterweight of the descending car.

Many historical systems used this efficiency and took it one step further with systems exclusively powered by water and gravity.

The monster footprint of digital technology

  

The power consumption of our high-tech machines and devices is hugely underestimated.

When we talk about energy consumption, all attention goes to the electricity use of a device or a machine while in operation. A 30 watt laptop is considered more energy efficient than a 300 watt refrigerator. This may sound logical, but this kind of comparisons does not make much sense if you don't also consider the energy that was required to manufacture the devices you compare. This is especially true for high-tech products, which are produced by means of extremely material- and energy-intensive manufacturing processes. How much energy do our high-tech gadgets really consume?

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.

Sunbathing in the living room: oven stoves and heat walls

Oven stoves are greener, more efficient, healthier, safer and cosier than all modern heating systems. Why are they gone and how do we get them back?

An oven stove is a very efficient and robust oven that radiates heat all day. In the US it was introduced only 20 years ago, but in Europe the technology is almost one thousand years old. Especially in Russia, Scandinavia and Central Europe the oven stove has a long and rich tradition.

In the 18th century, several European governments financed research to improve the technology, as a way to overcome an acute shortage of firewood: ecotech before the term existed. However, its further development and distribution was thwarted by the arrival of coal, gas and oil. Oven stoves are large, heavy and slow, but they offer so many advantages that they – again - deserve to be subsidized by the government.

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.

The age of speed: how to reduce global fuel consumption by 75 percent

If we cut the average speed of all vehicles by half, fuel consumption would decrease by a whopping 75 percent.

Breaking speed records was an almost daily occurence throughout the 20th century. Cars, ships, planes and trains became faster and faster, year after year. Because the power needed to push an object through air increases with the cube of velocity, this race to ever higher speeds raises energy consumption exponentially.

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. Lower speeds combined with more energy efficient engines, better aerodynamics and lighter materials could make fuel savings even larger.                                                                     Picture : Mando Maniac