Showing posts with label solar. Show all posts
Showing posts with label solar. Show all posts

Sunday, January 25, 2015

organs on chips

The slightly delayed January issue of Chemistry & Industry includes my feature on chip-sized microfluidic models of human organs, mainly based on the amazing work that's been done at the Wyss Institute at Harvard in recent years. This may well revolutionise medicine and make animal testing redundant.

Chips with everything
Chemistry & Industry January 2015, pp 28-31
Free access to full text

Image: Harvard's Wyss Institute

In the same issue, there is also my review of the book

The burning answer: a user’s guide to the solar revolution
by Keith Barnham (Weidenfeld & Nicolson 2014)

The solar revolution
Chemistry & Industry January 2015, pp 48-49
Restricted access

Here's a snippet from my (long essay) review:

"In fact, Barnham delivers three books for the price of one: a popular science book on the historic developments that led to our current energy technologies, then the “user’s guide” of the subtitle, an analysis of the present day situation in the renewable energy vs. climate change field complete with a manifesto for the revolution, and finally a look at what should and might happen in those crucial 15 years ahead of us, which may well decide the long-term success of our civilisation."

Monday, July 07, 2014

solar fuel

My latest feature in Current Biology discusses artificial photosynthesis and the quest to produce transport fuel from renewable energies:

Closing the carbon cycle

Current Biology Volume 24, Issue 13, pR583–R585, 7 July 2014

Free access to full text and PDF link

own photo

Tuesday, May 24, 2011

Germany's nuclear exit strategy

Immediately after the Fukushima disaster, the German government performed a spectacular U-turn on nuclear energy. Just six months after drawing up a plan to slow down the planned closure of its remaining nuclear power stations, Germany now looks likely to speed it up, and may well do so by 2020. This would make Germany the first country to abandon nuclear energy after using it for decades, so it would set an interesting example for others to study and possibly to follow.

Read my news feature which is out in Current Biology today:

Energy U-turn in Germany
Current Biology, Volume 21, Issue 10, R379-R381, 24 May 2011
doi:10.1016/j.cub.2011.05.003
Summary and open access to pdf file.

This is also one of the rare articles to be printed with one of my own photos, namely this one:

solarhaus

(click image to see larger versions in my flickr photostream)

-------
Updates:

31.5. German government gives detailed plan for 2022 exit: Guardian report.

25.5. Pleased to note that the Swiss government is now moving in the direction I anticipated and taking steps towards a phase-out of nuclear energy (see this Guardian report. It would have been slightly embarrassing if they had changed their mind in the weeks between my writing the article and its publication.

The UK, meanwhile, has decided to dump radioactive waste in an ordinary landfill site. What a brilliant idea. I wonder whether nuclear energy expert Homer Simpson was involved with the planning? And seeing that the company involved is called Augean, will they divert a river to wash the waste into the sea?

Wednesday, March 03, 2010

the wrong kind of incentive?

(updated Fri 5.3.2010)

I used to admire George Monbiot, but in his column this week he delivers a general bashing of feed-in-tariffs which includes a few points I have to disagree with. Feed-in-tariffs are a scheme first introduced in Germany 10 years ago and since then copied in around 60 countries and several US states, by which private households that generate their own electricity can sell it back to the electricity provider and get paid more than they would pay to buy the equivalent energy, thus providing a cash incentive for the installation of private solar panels, wind turbines, etc.

As of 1.4., the UK introduces a similar scheme, which Monbiot now rubbishes, dismissing the German scheme along with it. Addressing his criticism point by point:

1) The UK scheme (unlike the German one) is designed to deliver a guaranteed return on the householder's investment, which means that the most inefficient methods of producing energy get the highest subsidies. I agree that this is a fatal flaw in the UK scheme. (I think the German scheme is also different in that it pays generators _only_ for the excess electricity they feed back to the net, not for what they use themselves. So for German householders it pays to generate _and_ save energy.) Trust New Labour to do something ten years late and then get it wrong.

2) Compared with other options, Monbiot says, solar PV (photovoltaics, i.e. using sunlight to create electricity, as opposed to heat) is the most expensive way of saving a given amount of CO2 emission. Apart from the fact that some of the cheaper options include unpalatable things like massive use of nuclear power, I tend to think that we need all reasonable options, including expensive ones. He points out that replacing incandescent light bulbs with energy-saving ones actually saves money and CO2. Well, we did that in 1986, but it hasn't stopped global CO2 emissions from going up further.

3) Monbiot says that in Germany carbon saving by PV is zero, because under the carbon trading act other industries can release more CO2 and compensate any effect. But that would apply to everything anybody might do, so it's a flaw in the trading act rather than a shortcoming in PV specifically.

4) He says the scheme subsidises the "fashion accessories" of rich people (by which he means home owners, which is strange as in the UK around half the households live in their own home, and most wouldn't consider themselves to be rich) at the expense of poor people who can't use the incentive and have to pay for it through higher electricity bills. While there is a small grain of truth in that, I would argue that the better-off part of the population would tend to waste electricity (eg by having several refrigerators instead of one, and several huge flat screen TVs), while the poor would be aware of their electricity bill. So unless I get to see hard data, I would assume the scheme penalises people who waste electricity and isn't particularly hard on poor people.

5) In the last part of the column, Monbiot claims that criminals could easily abuse the system by using electricity off the net to sell it back to the net at a multiple of the price. A few lines further down, though, we learn that the FIT scheme introduced in the UK now doesn't involve metering the electricity fed back to the net but is based on estimated output calculated from PV capacity. As I understand it, this would mean the criminal scheme outlined above wouldn't work.

6) Monbiot is right to point out that the success of PV depends on latitude, i.e. sunshine -- when dismissing the German scheme he may have forgotten to consider that Germany is actually further south than the UK, and does have quite warm summers.

7) Monbiot argues that PV is useless in the UK as it produces power at times when it is least needed, i.e. during summer days, as opposed to winter evenings. However, as most of the UK power is produced by fossil fuels which can be burnt any time or stored if they aren't, every bit of solar power generated even on a hot summer day saves fossil fuels from being burnt. Even more so, as the sunshine intensity is predictable in the short term, so fossil fuel plants can turn down their capacity on those sunny days.

8) another advantage for Germany that Monbiot fails to acknowledge is that as an early mover, the German PV industry has hugely benefited from the scheme and is, I believe, second after China globally. This, of course, doesn't help the UK government which ineptly copied the scheme ten years later.

9) considering that he's been banging on about growing his own green food for years, it is also curious that he doesn't appreciate people may like the idea of producing their own green energy.

I've published a (somewhat more positive) piece about the German scheme in Current Biology a few years ago, which is on restricted access here (also see the relevant blog entry).

PS (4.3.): 10. Monbiot says the German incentives are being scaled down this month because the scheme wasn't working. I haven't researched that yet, but I would suspect that they were scaled down because the black/yellow coalition (conservative / neoliberals) saw the opportunity to cut back something the red-green coalition had put in place in 2000. Also, there may have been a 10 year guarantee which has now run out, not sure. Plus, as the scheme has been very successful in kick-starting the solar industry, the govt. may argue that it's done its job and isn't needed on a similar scale any more. Will have to look into that.

PS (5.3.): yesterday's Guardian carries a response from Jeremy Leggett (who works in the PV industry and is the editor of the book "The solar century" which I reviewed last year):
Solar panels are not fashion accessories,
rejecting Monbiot's claims in four points. Actually, I was considering to submit my 9points to the response column, but then thought Jeremy Leggett is surely going to write something (and he's more qualified). Psychic powers working well this week!

Also in yesterday's edition is an article on the finance pages suggesting that a crucial piece of legislation needed to make the FITs work has been delayed, so the whole thing may still go off the rails. Better wait before I top up that mortgage. This finance article refers to Monbiot as a "green campaigner". Not so sure about that any more, as he now supports nuclear and bashes solar power.

Tuesday, February 23, 2010

searching for a second genesis

One of the new(ish) things I learned at the Royal Society discussion meeting in January is that the "search for a second genesis" is now a unifying theme that covers SETI, extrasolar planets, solar systems exploration, and even the study of extreme environments on Earth. I've explained this philosphy of astrobiology in a shortish news feature, which is out in Current Biology today:

High life
Current Biology, Volume 20, Issue 4, R129, 23 February 2010
doi:10.1016/j.cub.2010.02.005
abstract and restricted access to pdf file


PS: for the same issue, I also wrote a short piece on UK feed-in tariffs, which was merged into the climate change piece:

Climate change attack
Nigel Williams
Current Biology, Volume 20, Issue 4, R125-R127, 23 February 2010
abstract and restricted access to pdf file

Wednesday, October 28, 2009

solar century

I reviewed "The solar century" by Jeremy Leggett (ed.) for Chemistry & Industry, a nicely illustrated plea for going solar, with all the arguments why we must and how we can. That's in issue 20, (26.10.2009), p 29. Probably premium content, but here's a snippet from the end of my review:

Alas, the solar century has had a rather sluggish start in some parts of the world, but it could still happen. And with the evidence for human-induced climate change piling up, it is becoming increasingly obvious that our century must become the solar century, or more widely defined, a renewable energy century, if it isn’t to become a different book title, namely our final century.

Friday, August 14, 2009

energy solution

According to plans drawn up by the DESERTEC consortium, most of Europe's energy needs could be supplied from large scale solar power plants in North Africa and the Middle East. The plan is based on concentrating solar-thermal power plants and a high-voltage direct current (HVDC) grid. It has recently come a step closer to realisation with the signing of an agreement between a dozen major companies, launching the Desertec Industrial Initiative.

Read my story in this week's issue of Current Biology:


New grids on the block
Michael Gross
Current Biology, Volume 19, Issue 15, R626-R627, 11 August 2009
doi:10.1016/j.cub.2009.07.043
Summary:
Meeting both carbon emission targets and energy demands may be feasible with DC cables connecting power-thirsty cities to sun-drenched deserts.
[PDF] (restricted access)

Sunday, May 03, 2009

towards tandem solar cells

Dye-sensitized solar cells (DSSCs), invented by Michael Grätzel and Brian O’Regan in 1991, are recognized as a cost-efficient alternative to traditional photovoltaic cells. Typically, they are based on n-type semiconductors (e.g. TiO2) as the anode where the light energy is harvested. More recently, researchers have introduced the reverse type of solar cell, where p-type semiconductors (e.g. NiO) act as a light-harvesting cathode. N- and p-type semiconductors are doped with small amounts of negative or positive charge carriers, respectively. In DSSCs, the organic dye molecule takes over the function of doping, injecting electrons or holes, respectively, into the semiconductor material.


Now the group of Licheng Sun and Anders Hagfeldt at the Royal Institute of Technology at Stockholm , Sweden , have more than doubled the efficiency of p-type semiconductor DSSCs, opening up the prospect of using them in tandem with the traditional Grätzel cell, i.e. in an arrangement where both electrodes contribute to the conversion of solar energy.


Read my story in Chemistry World (open access).

Friday, September 19, 2008

going green as if it was 1993

I don't want to engage in any flag waving, but I need to get rid of this rant before the year is out, so here it goes:

We moved from Germany to the UK in 1993, and with all the "going green" discussion happening here in the UK now in 2008, it has struck us that the state of progress on green awareness here and now is very much like Germany 1993. Councils collecting plastic for recycling, shops offering multi-use cloth bags to buy instead of handing out plastic bags automatically, occasional appearance of solar panels on private houses, acknowledgement of green issues by leading politicians, all these things have only become noticable here in the last months, and all of these happened in Germany before we moved away in May 1993.

So I now declare the UK to be 15 years behind on green issues, and if any politician here claims leadership in this field again I'll knock him over the head with a solar panel ... just kidding. Rant over now.

Friday, June 13, 2008

solar motor

Researchers in Japan have built an extremely cool motor, driven purely by the effect that light has on certain molecules, but turning wheels of visible size.

Read my story here.

Thursday, August 23, 2007

(solar) power to the people

Way back when in the eighties, when I was young and green, Germany's Green Party, untainted by real government responsibility, had lots of nice policies in their programs, including the one that people who produce renewable energy small scale, e.g. with a solar panel on their roof, should be entitled to sell any spare electricity back to the providers. Very simple, very obvious, though we never really believed we'd get through with this in a capitalist world.

When the red-green coalition came to power, it very sneakily introduced this idea into a new law governing energy provision (living abroad by then, I actually missed it when it happened), without creating the storm I would have expected.

These so-called feed-in tariffs have since then become a major success story, as they have made private photovoltaic cells economically attractive, plus the idea has been copied by legislators in many other countries -- as I found out to my surprise when I researched a news feature for Current Biology.

Read my story here:

Current Biology 17, No 16 (21.08.), R616
Germany goes for solar