Call for delay to biofuels policy

The UK's chief environment scientist has called for a delay to a policy demanding inclusion of biofuels into fuel at pumps across the UK.

Professor Robert Watson said ministers should await the results of their inquiry into biofuels' sustainability.

Some scientists think biofuels' carbon benefits may be currently outweighed by negative effects from their production.

The Renewable Transport Fuels Obligation (RTFO) is to introduce 2.5% biofuels at the pumps from 1 April.

Professor Robert Watson warned that it would be insane if the RTFO had the opposite effects of the ones intended.

He said biofuels policy in the EU and the UK may have run ahead of the science.

His comments in an interview with BBC Radio 4's Today programme appear on the day when a coalition of pressure groups from Oxfam to Greenpeace writes to the Department for Transport (DfT) demanding that the policy be delayed until after the review.

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Solar-power paint lets you generate as you decorate

A lick of solar-power paint could see the roofs and walls of warehouses and other buildings generate electricity from the sun, if research by UK researchers pays off. The scientists are developing a way to paint solar cells onto the steel sheets commonly used to clad large buildings.

Steel sheets are painted rapidly in steel mills by passing them through rollers. A consortium led by Swansea University, UK, hopes to use that process to cover steel sheets with a photovoltaic paint at up to 40 square metres per minute.

The paint will be based on dye-sensitised solar cells. Instead of absorbing sunlight using silicon like conventional solar panels, they use dye molecules attached to particles of the titanium dioxide pigment used in paints.

That gives an energy boost to electrons, which hop from the dye into a layer of electrolyte. This then transfers the extra energy into a collecting circuit, before the electrons cycle back to the dye.

While less efficient than conventional cells, dye-based cells do not require expensive silicon, and can be applied as a liquid paste.

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Power station harnesses Sun's rays

There is a scene in one of the Austin Powers films where Dr Evil unleashes a giant "tractor beam" of energy at Earth in order to extract a massive payment.

Well, the memory of it kept me chuckling as I toured the extraordinary scene of the new solar thermal power plant outside Seville in southern Spain.

From a distance, as we rounded a bend and first caught sight of it, I couldn't believe the strange structure ahead of me was actually real.

A concrete tower - 40 storeys high - stood bathed in intense white light, a totally bizarre image in the depths of the Andalusian countryside.

The tower looked like it was being hosed with giant sprays of water or was somehow being squirted with jets of pale gas. I had trouble working it out.

In fact, as we found out when we got closer, the rays of sunlight reflected by a field of 600 huge mirrors are so intense they illuminate the water vapour and dust hanging in the air.

The effect is to give the whole place a glow - even an aura - and if you're concerned about climate change that may well be deserved.

It is Europe's first commercially operating power station using the Sun's energy this way and at the moment its operator, Solucar, proudly claims that it generates 11 Megawatts (MW) of electricity without emitting a single puff of greenhouse gas. This current figure is enough to power up to 6,000 homes.

But ultimately, the entire plant should generate as much power as is used by the 600,000 people of Seville.

It works by focusing the reflected rays on one location, turning water into steam and then blasting it into turbines to generate power.

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UTILITY SCALE PHOTOVOLTAICS

If you can’t make rooftop photovoltaics pay financially without feed in tariffs, tax credits, accellerated depreciation, rebates, and subsidized loans - and even with all that it’s still barely better financially than just sticking to natural gas or coal fired grid electricity - how on earth can something like this succeed at the utility scale?
One reason solar energy still cannot compete financially vs. conventional energy is because the value of future energy output from a photovoltaic system is discounted when calculating, for example, an internal rate of return. But economic models that put a time-value on money - making receipts in the future not worth as much as receipts today - cannot necessarily be applied to energy.

A fairly stealthy, fast growing, vertically integrated photovoltaic company who is staking their strategy on utility scale applications is Optisolar, based in Hayward, California. Owning everything from the manufacturing (and the underlying thin film technology), to the solar fields they build, they have begun construction on what will be the largest photovoltaic field in the world to-date.

It’s interesting that the world’s largest PV array currently is the utility-scale 12-megawatt Erlasee solar park in Germany, and this new 50 megawatt plant built by Optisolar is going to be Ontario, Canada. Interesting because Germany and Canada aren’t necessarily considered the sunniest places on earth.

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