Wednesday 23 January 2013

The "Consequential Improvements" Quiz

Why the UK government should show greater courage on the Building Regulations

Take a look at the photo; then see if you can answer the quiz.  The photo is of the roofs of two semi detached houses taken three days after 25mm of snow fell.

Is roof insulation a hot topic at the Department for Communities and Local Government?
1.       (EASY) Which house has the better loft insulation?

2.       (MODERATE) Which of the two houses is privately owned, and which is social rent?

3.     (DIFFICULT) When the extension was recently built on the right hand house why wasn’t the loft insulation improved at the same time?   Why is the insulation in the new roof (lower roof to the right) just as poor as the old?
4.  (IMPOSSIBLE)  Why has the government dropped plans to use the building regulations to ensure that home-improvements also result in energy efficiency?

The government's flagship green policy, the Green Deal is not an incentive scheme, it is a financing mechanism.  Home improvements are financially neutral to the householder because the reduction in energy savings is offset by repayments of the loan.  If the Green Deal is going to succeed, then it will need incentives to encourage participation.  The £125m grant scheme recently announced along with the launch of the scheme is a start, but will not be enough on its own.

The consultation on changes to the building regulations included a suggestion that when people make home improvements such as extensions, that they will have to improve the energy performance of the whole property.  This idea was a brilliant example of joined-up-thinking in policy development, because the home-improvers would incur no extra costs because the Green Deal could pay for extra insulation, new windows and beautiful solar panels on the roof.

Unfortunately, this idea was branded a “Conservatory Tax” by the Daily Mail, and the resolve of the government seems to have melted away like snow on a poorly insulated roof.

Saturday 12 January 2013

Down to Earth – Will Scarce Rare Earths Impact the Solar Industry?

Recent concerns about continuing availability of “rare earth” elements and the impact on the solar PV industry

Yttrium, Cerium, Promethium, Neodymium; hanging out in an intimidating gang at the bottom of the Periodic Table, excluded from school chemistry lessons, the exotic-sounding names and even the collective name for the fourteen “Rare earth elements” conjure up the idea of materials made precious by extreme scarcity. 

Not so scary now?

A rash of headlines in recent times (examples: 1, 2, 3) have highlighted the importance of these materials for producing the gadgets essential for modern life.  Items such as displays and batteries for mobile phones and laptops rely upon small amounts in their manufacture but also technologies in the rapidly emerging clean energy sector.  According to these reports permanent magnets used in wind turbines and electric motors, chemical formulations for low energy light bulbs, and (most importantly, of course) solar cells apparently depend on these rare earths.

The reason for the headlines?  China controls 90% of the production of rare earths and it was becoming clear that it wasn’t averse to using them for political leverage.  A sensitive dispute with Japan over which country owns the Senkaku/Diaoyu islands, a few specks of land in the East China Sea, resulted in China restricting the export of rare earths to the fury of the Japanese whose high technology industries use loads of the stuff.

So, is it right to worry that the solar industry is built on shaky foundations? Are rare earth elements essential for solar cells?  Would we have been better off in an industry that relied on hummingbird tears and mermaid’s toenail clippings to make its products?

Well, it turns out that rare earths aren’t all that rare, and that solar cells don’t actually use them anyway.

How Rare are Rare Earths?

Rare earths are actually relatively abundant in the Earth’s crust; about as plentiful as copper.  The reason for the name is that they are well dispersed, and not often found in concentrations that can be economically extracted.

However, rare earth minerals have been mined in India, Brazil, South Africa and the USA as well as China.  China only has 30% of the world’s rare earth deposits.  However, in a move that will resonate with some in the solar PV industry, Chinese producers came to control production by supplying at much lower price, causing mines in other parts of the world to shut down

As China seeks now to benefit from its control of the market by restricting supply and increasing prices, other producers are already starting to come back on line.  For example Molycorp began work in 2011 to bring its Mountain Pass mine in California back into rare earth production.

Do Solar Cells Even Need Rare Earth Minerals?

I’ve had a good look around, and the only reference I can find to rare earth elements in solar, is that Cerium Oxide is sometimes added to glass used in solar modules to increase UV absorbtion.

It appears that the reason so many people have written that rare earth are ‘essential’ for solar cells can be traced to a report written by the US Department of Energy in 2010 “Critical Materials Strategy”. 

Two forms of thin film PV materials were identified in the report as using critical (but not rare earth) elements.  CIGS thin films use indium and gallium, and CdTe films use tellurium.  (See the table below, summarizing the materials considered).  The report then goes on to conclude that indium, gallium and tellurium all come from diverse sources.

In 2010, thin film PV dropped to only 13.5% of the market in the face of price competition from crystalline silicon cells, and CIGS and CdTe PV are only two thin film technologies among many.

So, a fine example of how journalism works.  Two forms of the less widely-used types of solar PV get mentioned in a report that assessed strategic materials such as rare earths; rare earths hit the headlines in a trade war; and we end up with articles that suggest we’re going to run out of the raw materials for solar PV. 

Panic over?

Wednesday 2 January 2013

Solar Joins the Big Guns

Notable by its absence from the Department of Energy and Climate Change’s (DECC’s)  2011 Renewable Energy Roadmap, has solar energy fared any better in the 2012 update?  The solarblogger investigates.

On December 27th DECC released an update on the UK’s progress towards meeting binding targets from the EU to generate 15% of all energy from renewable resources by 2020.  They also shared current thinking on how this target might be met.

Plenty left to do

Progress to Date

In 2011, renewable energy rose to 3.8% of all energy consumption from 3.2% in the previous year.  The lion’s share of this increase came from renewable electricity.  Its share of all generation rose 27% to 38 TWh, and now represents 10.4% of all UK electricity generation.

TWh = Terawatt-hours, equivalent to one thousand GWh (gigawatt-hours) or one billion kilowatt-hours – see “Slippery when Watt
The average house uses around 4,200 kilowatt-hours per year – see “How much electricitydoes the average house use?

Wind turbines contribute 17 TWh, nearly half of the renewable electricity generation, with a further 14 TWh generated from burning biomass, and the remainder from hydro-electricity.  PV solar generation currently produces a just-visible slice in the bar chart.

Renewable heat on the other hand trails behind, at 14 TWh of energy, an increase of only 5%.  Although heat accounts for 46% of the UK final energy use, it is only recently that government support mechanisms that reflect its importance have been brought forward.

The Renewable Heat Incentive (RHI) for commercial buildings has been in place for just over a year with mixed results, and will be followed by an RHI for domestic buildings in the late summer of 2013.



DECC reckons to have reasonable visibility of the future deployment pipelines for wind and biomass electricity generation. 

There’s just under 5GW of biomass generation plant under construction or in planning, to make a total of 8GW of generation capacity.  Assuming a similar load factor to the current capacity, this would deliver around 33TWh/year.

If all the wind capacity identified in DECCs pipeline is developed, that would total 26GW, and produce annual generation of about 68TWh assuming a 30% capacity factor.

Just these two technologies, plus the existing hydroelectric capacity could then contribute 108TWh/year, or around 30% of current electricity demand.

This may sound a like a real achievement – and it is, but when you consider that electricity for lighting and appliances accounts for only 8% of final energy use of the UK you can appreciate the scale of the challenge we face.  The goals for the other two major energy uses – heating (46% of final energy) and transport (41% of final energy) need to be similarly ambitious, and this is where the roadmap starts to feel rather thin.

While 28 pages are devoted to renewable electricity, only 7 are spent on heat and 4 on transport.

Renewable Heat

The Renewable Heat Incentive (RHI) is the main mechanism for pushing forward the adoption of low carbon heating technologies. 

A quick look at the Ofgem RHI website shows that in its first 13 months of operation, the scheme has so far paid out on 0.066 TWh of renewable heat generation, a rather pitiful contribution compared to the electrical technologies, but hopefully one that can grow rapidly as awareness of the scheme increases and consistent support is sustained over a significant period of time.

98% of heat under the RHI is currently from biomass boilers.  The scheme has so far been spectacularly unsuccessful at stimulating take up of either solar heating or heat pumps.  See my blog article on the success of the RHI to date here.

The solar industry has greater expectations for a domestic renewable heat incentive, which after many delays, is expected to launch in Summer 2013, see my blog article on the consultation here.


The transport section of the report is the thinnest, with little in the way of concrete action to discuss.  This reflects the global nature of the challenges to develop new automotive technologies, and the need for technological breakthroughs, particularly in energy storage which are acknowledged in the report.

So What for Solar?

The document was, on the whole, pretty good news for solar energy in the UK.

The potential of Solar PV to make a significant contribution to the UK energy mix is recognized for the first time, with an estimated 2020 deployment of between 7 and 20GW, contributing between 6 and 8 TWh per year.  DECC believes that grid-balancing challenges and the evolution of PV costs over the next few years will determine the level.

DECC also revealed their intention to develop a PV Strategy document during 2013.

For solar thermal technology, the best news was that DECC re-iterated their determination to launch a domestic RHI in summer 2013, listing it as a key priority.