The much debated, tweeted, blogged and indeed refreshing government legislation, the feed-in tariff, which is to become reality on April 1 could transform micro-generation from cottage industry to nationwide norm within the next few years according to Steven Harris. Harris, as head of low carbon technologies at the Energy Savings Trust (EST) believes that with the tariff legislation in place, the UK will be in good shape to see a large scale uptake of renewable technologies, something which he believes only a few years ago would have been incomprehensible.

“The poor old cottage industry of renewable energy will not know what’s hit it. People could be forgiven for waiting to install these technologies up until this point, but once the tariff comes in, things could change rapidly,” states Harris who certainly knows how difficult it has been to bring about a change in attitudes towards the viabilty and importance of green technologies.

Harris who along with his colleague Bill Dunstar created the BedZed village project featuring carbon neutral housing in the Surrey commuter town of Wallington ten years ago can easily recall the derision which green ideas were met with at the time. The project which was shortlisted for the Stirling Prize in 2003 highlighted the potential feasibility of sustainable materials and carbon neutral building at a time when such ideas were far from the mainstream. Harris recalls,

“It’s amazing when you sit in meetings now; people are saying exactly the same stuff that was laughed at when we were starting BedZed. Back then, things such as using reclaimed materials, sustainability assessments, local sourcing, having an ecological footprint… they were just not on the construction agenda, let alone the housing agenda.”

With the introduction of the feed-in tariff at the beginning of next month the situation has changed dramatically for micro-generation projects such as BedZed pioneered by Harris and Dunstar. The tariff will offer small-scale generators of green energy guaranteed, premium rates for energy fed-back in to the national grid and will thereby seek to offset the obvious costs involved in installing renewable technologies. With annual returns of £500 expected for households with solar PV installed, the industry is hopeful that the solar industry has the potential to take off with the backing of the tariff.

Steven Harris certainly believes that solar micro-generation could become widespread with the tariff mechanism incentivising investment and see the BedZed project become reality within the next decade.

“Solar technology has really moved forward. In China, it’s illegal not to put thermal solar on your roof, but they have the advantage of a totalitarian state. The fact that they have to manufacture panels for billions of people has really driven down the cost of solar. I know when we first started BedZed, the payback on a panel was around 75 years; now it’s about 12.”

The Chinese National Energy Administration has announced via the state run newspaper China Daily that they will be seeking to produce around 15 per cent of all the country’s energy by renewable means within the next 10 years.

China, despite being criticised for its heavily industrialised, polluting economy and images of Beijing obscured by dense smog during the 2008 Olympic Games, the government is taking proactive steps towards reducing carbon emissions with measures that would shame certain other attendees of the Copenhagen climate summit.

With the growing realisation of the fallibility on basing the huge Chinese economy on fossil fuel imports which could become untenable within the next 25 years, the Beijing government is planning to spend billions of dollars in investing in solar and wind farm sites in addition to research projects which could keep China at the cutting edge of green energy generation.

Renewable energy generation grew by 1 per cent in China in the last 12 months with the government hopeful that figures will grow from the present 9.9 per cent to 15 per cent by 2020. The Chinese government is keen to diversify its economy as well as its means of energy generation with the dual purpose of slowing the effects of climate change and making the economy more robust in the face of any potential fuel crises which could arise in the near future.

In spite of passing legislation designed to have an immediate impact on renewable energy uptake such as the feed-in tariff, a mechanism to incentivise investment in green technologies, government spokesman Zhang Guobao is realistic about the timescales involved in such projects. Speaking to China Daily, Zhang commented that,

“Power projects take a long time to be up and running, and we are basically allowing five years to complete them although it is a 10-year program, otherwise, the facilities cannot be put into use by 2020.”

Zhang added, “It appears that some local governments approved energy-guzzling projects during economic crisis so only by fully implementing our energy saving regulations can we realize economic growth with less energy consumption.”

The winter months have brought lots of snowfalls, or as they are known in the world of solar energy, ‘shading events.’ You might be forgiven for wondering what exactly happens to the performance of solar panels when they are covered in snow, or anything else for that matter.

Shading is a big issue for solar arrays. A small amount of shading on one solar panel can result in a big power loss for the entire system. This is because of how they are connected together; a solar panel is made of a number of solar cells connected in series. Each solar cell has a current of around 8 Amps and a small voltage of 0.6V or so when under full sunlight. For those who remember their physics classes from school, this means that when they are connected in series the voltages add up but the current stays equal. Solar panels are then connected together in series to make a string, so the current still stays the same (on large arrays multiple strings are connected in parallel).

What this means is that if one solar panel, or even one cell of one solar panel is affected, it will affect all the others. When a cell is shaded its output current decreases, which means the current for all the other cells and modules is also limited. So one small patch of shade can disproportionately reduce the power output of the whole system.
This effect can be limited by a number of means.

The best way is to make sure your solar panels are not going to be shaded in the first place. This should be checked as part of the site survey, conducted by your MCS accredited installer. You should ensure that nothing will shade the modules during the middle of the day, when your system should be producing the most energy. Shading can be checked using a special design tools that show the path of the sun behind various shading objects. This can be either a lens that shows the horizon and path of the sun in front of you, or a full design software package that uses photographs of the surroundings.

With snow it does help to clear it off. But there isn’t usually much sun when its snowing, and if the sun does come out, the snow melts pretty quickly.

If you cannot eliminate shading as is often the case in built up areas, there are several technologies that can limit the effect of it. Many solar panels now include bypass diodes that disconnect groups of solar cells if they are shaded. It is fairly crude but often works well. When you buy solar panels make sure to ask about bypass diodes.

A second technology that is not available yet in Europe but soon will be is distributed conversion. Here, rather than have power electronics (like the inverter) positioned all in one place, you have some electronics placed on each module. This allows each module to operate independently. One company in the US called Enphase claims this technology increases power output by upto 25 percent.

These are all things to bear in mind when buying a photovoltaic system.

In a bid to prevent a shortfall in rate payments for pioneers in small scale renewable energy investment, Good Energy has promised to continue to pay its generators 15p /kWh rather than the 9p / kWh set out in the recently announced tariff legislation.

Good Energy, dealing solely in renewable energy has announced that the government’s recent tariff scheme would harm their so-called ‘pioneer’ generators who installed their renewable technology before the cut-off date of July 15, 2009. Under the new tariff regime to come into effect in the Spring of this year, these pre -July 15 customers would only be eligible for a 9p/kWh payment for units of renewable energy compared to a payment of 41.3p/ kWh for installations after this date.

In a bid to keep pioneer installors viable until when they hope the government will amend their pre July 15, 2009 rule, Good Energy will continue to pay these generators the previous 15p/kWh rate. Currently, Good Energy sees itself as a market leader in renewable energy uptake incentivisation and wants to continue awarding attractive incentives for smale scale installors of renewable energy technology. Leading the way in 2004 with their renewable energy incentive scheme HomeGen, Good Energy believe that the government’s scheme is treating long term micro-generators unfairly.

CEO of Good Energy, Juliet Davenport, announced:

“It’s outrageous that the new FiT only pays the highest reward to new generators – Good Energy believes that the early adopters of microgeneration technology should also be recognised for their pioneering attitude and taking a lead.

That’s why we’ve decided to continue paying our existing accredited HomeGen generators 15p a unit for all the electricity they generate and lobby to change the government’s mind.

It’s outrageous that the new FiT only pays the highest reward to new generators – Good Energy believes that the early adopters of microgeneration technology should also be recognised for their pioneering attitude and taking a lead. That’s why we’ve decided to continue paying our existing accredited HomeGen generators 15p a unit for all the electricity they generate and lobby to change the government’s mind.”