Erstellt am: 29. 1. 2013 - 15:50 Uhr

Cracking the key to clean, green power

Reality Check: Liquid air, Australia's extreme weather, US immigration, Brazil club safety, Iran arrests journalists

NASA / Radio FM4

Clean, Green & Forever

Die Woche der erneuerbaren Energien auf FM4.

Alles zum Nachlesen auch auf fm4.orf.at/greenenergy

It's renewable energy week on FM4, which means that all this week we will be featuring stories about sustainable energy under the title "Clean, green and forever".

There can't be many right thinking people on earth who don't embrace the idea of renewable energy. I can imagine a great many readers of this site would share my own ideal of being able to "live green", and enjoy modern comforts without taking a toll on the environment.

However, when we get down to practicalities, there are problems. Natural energy sources, like wind, water and sun, are notoriously fickle and unpredictable. That means you need to be able to store the energy at one time, and use it later.

A revolutionary solution to this problem is now being presented by the Institution of Mechanical Engineers in Britain. It uses the same basic technology as the steam engine, but instead of taking water and heating it up, the idea is to take air and cool it down until it becomes liquid. As the liquid air warms up, it expands and turns back into a gas - and this process can be used to drive turbines to create electricity in the same way that steam can.

Applying this to renewable energy, instead of trying to store energy in batteries, excess energy is used to make liquid air. That liquid air can then be warmed up and used to power turbines and generate power when it is needed. This way, "wrong time" energy can be converted into "right time" energy with an efficiency of up to 70%.

That makes the liquid air solution clean, green and, for all practical purposes, forever. It is only not forever in the sense that the air might run out but, of course, if that happens, we won't have to worry about energy.

Tim Fox of the Institution of Mechanical Engineers explains liquid air energy to Joanna Bostock.

US Immigration

The planned immigrations reforms under discussion in the USA. Priscilla Huff reports from Washington D.C.

Brazil clubs

Following the deadly fire at a disco in Santa Maria, we take a look at the Brazilian club scene with Joyce Muniz, a DJ, singer and music producer from Sao Paolo. She says that while clubs in major cities like Rio or Sao Paolo are strictly controlled and have excellent safety regulations, in more remote places and in the countryside, there is little regard paid to safety, especially where there is money to be made.

Iran arrests journalists

Over a dozen journalists are arrested in Tehran, accused of cooperating with foreign Persian language media organisation. Our Tehran correspondent, Christian Schüller, explains why this is a particularly sensitive time for the Iranian regime.

Australia 's fire and floods

EPA/Str

Thousands of people have been forced from their homes by flooding in the town of Bundaberg in Queensland...

EPA/TRACEY NEARMY

...while bush fires still claim blaze in Victoria and New South Wales

Bush fires are still raging in parts of the country which are sweltering in record high temperatures, while other areas are under water. What do the extremes in Australia mean for the rest of the world?

FM4 Reality Check

Monday to Friday from 12.00 to 14.00, and after the show via Podcast or fm4.orf.at/realitycheck.