High Speed Trains are Killing the European Railway Network The introduction of a high speed train connection invariably accompanies the elimination of a slightly slower, but much more affordable, alternative route, forcing passengers to use the new and more expensive product, or abandon the train altogether.
As a result, business people switch from full-service planes to high speed trains, while the majority of Europeans are pushed into cars, coaches and low-cost airplanes.
How Sustainable is PV Solar Power? It's generally assumed that it only takes a few years before solar panels have generated as much energy as it took to make them, resulting in very low greenhouse gas emissions compared to conventional grid electricity.
However, a more critical analysis shows that the cumulative energy and CO2 balance of the industry is negative, meaning that solar PV has actually increased energy use and greenhouse gas emissions instead of lowering them.
The problem is that we use and produce solar panels in the wrong places. By carefully selecting the location of both manufacturing and installation, the potential of solar power could be huge.
How Sustainable is Stored Sunlight? One of the constraints of solar power is that it is not always available: it is dependent on daylight hours and clear skies. In order to fill these gaps, a storage solution or a backup infrastructure of fossil fuel power plants is required -- a factor that is often ignored when scientists investigate the sustainability of PV systems.
Whether or not to include storage is no longer just an academic question. Driven by better battery technology and the disincentivization of grid-connected solar panels, off-grid solar is about to make a comeback. How sustainable is a solar PV system if energy storage is taken into account?
Why We Need a Speed Limit for the Internet In terms of energy conservation, the leaps made in energy efficiency by the infrastructure and devices we use to access the internet have allowed many online activities to be viewed as more sustainable than offline.
On the internet, however, advances in energy efficiency have a reverse effect: as the network becomes more energy efficient, its total energy use increases. This trend can only be stopped when we limit the demand for digital communication.
Who killed the electric grid? Fast-charging electric cars generate lots of excitement, but what seems to be forgotten is that they can lead to a fabulous amount of peak demand.
Urban windmills harm the environment & 12 small windmills put to the testA small windmill on your roof or in the garden is an attractive idea. Unfortunately, the financial payback time of micro wind turbines 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.
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. Maybe this time around we could sort this out before the damage gets done?
The monster footprint of digital technology 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.
Bike powered electricity generators are not sustainable When operating a bicycle generator you are basically pedalling to produce the energy required to manufacture the battery.
The status quo of electric cars Electric motors and batteries have improved substantially over the past one hundred years, but today's much hyped electric cars have a range that is - at best - comparable to that of their predecessors at the beginning of the 20th century.
Carbon sequestration: bury the idea, not the CO2 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.
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?
The ugly side of solar panels In some cases, producing electricity by solar panels releases more greenhouse gases than producing electricity by gas or even coal. Solar panels don't come falling out of the sky - they have to be manufactured. Similar to computer chips, this is a dirty and energy-intensive process.
How Sustainable is Digital Fabrication? While digital machine tools have been embraced by many, including some environmentalists who say the technology can be more sustainable, it's important to consider the very high energy use of digital machine tools. Compared to the earlier generation of human-controlled machine tools, CNC machines use much more power, and the potential to improve their energy efficiency is very limited.
Planes on wheels : high speed trains Trains are considered to be much more environmentally friendly than aircrafts. Unfortunately, they lose their ecological advantage when speed goes up. And train companies in Europe and Japan seem to be obsessed by speed.
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. LEDs might be useful, but they almost ever introduce lighting in places and situations where there was no lighting before.
Why the electric car has no (wireless) future The only possible green future for electric cars is a wired future: hooked up to the overhead lines, like trolleybuses and bumper cars.
Why bottled water is good for the environment 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.
Cars on hot air Following the hype on hydrogen - meet the car on compressed air.
Water eats energy Desalination – the process of turning seawater into fresh water - is increasingly becoming the world's solution to a growing water shortage problem. But if we count on the oceans to fulfill our future need, we have to find an extra 30.000 terawatt-hours of energy - twice the current global electricity production figure.
Faster internet is impossible Internet users continually need faster connections to surf the web at the same speed.
Supercomputers reach their limits Supercomputers are becoming ever more important in scientific research, the financial world and big business. Their processing speed keeps growing. But even if we take into account future energy-saving technologies, the electricity use of these machines will become an insurmountable obstacle in 10 to 15 years time - says Alan Gara, developer of the world’s most powerful supercomputer.
Imagine you put a portable hard disk of 500 gigabytes in your backpack and start walking. In which cases are you faster than your internet connection?