Page last updated at 20:18 GMT, Monday, 25 February 2008

Zero carbon goal needs firm foundation

Imtiaz Farookhi
Imtiaz Farookhi

There is no "magic bullet" solution when it comes to meeting the UK government's ambitious target of making new homes "zero-carbon" by 2016, says Imtiaz Farookhi. In this week's Green Room, he argues that poor use of technology will be just as bad as doing nothing at all.

Building site (Image: PA)
We must ensure that consumers of the future do not suffer from short-sighted decisions and the failure to use technology in the right place
The UK house building industry faces a serious challenge.

With about 27% of the nation's energy used in homes, the sector has turned to cutting-edge innovations to meet government targets for all new homes to be zero carbon by 2016.

The target is clearly ambitious, but there is no "magic bullet" solution when it comes to domestic renewable energy.

Therefore, our message is one of caution; the last thing we can afford to do is create homes that are not fit for purpose.

The successful implementation of microgeneration and renewable energy technologies is vital if we are to ensure that the work of the housing industry matches the government's aspirations.

Obviously, communities and homes of the future that we design and build today must deliver on the environmental promise to reduce carbon emissions.

Graphic showing household energy consumption (BBC)

But we must ensure that consumers of the future do not suffer from short-sighted decisions and the failure to use technology in the right place and for the right reasons.

We cannot risk a situation where one, two, or three generations of consumers will have to live with the legacy of poor decisions made today.

The NHBC Foundation is committed to ensuring that the industry has the tools it needs and the research data it requires to be able to make sound, well thought-out decisions which meet the aspirations of both homeowners and the government.

Tools for the job

The purpose of our new report, A Review of Microgeneration and Renewable Energy Technologies, is to ensure that builders and developers understand that not all options that are currently available will be suited for every development.

Futuristic eco-home (Image: PA)
Technology, if used properly, can deliver massive carbon savings

Our research has made it clear that much more thought and planning is required in order to gain the maximum benefits from the technologies that, although currently in their infancy, are likely to be incorporated into future zero-carbon homes.

The report evaluates eleven types that can help us cut carbon emissions on the domestic front.

These are: biomass, solar photovoltaic, solar hot water, wind power, ground source heating pumps, air source heating pumps, absorption heat pumps, small-scale hydroelectric, micro-combined heat-and-power, renewable combined heat-and-power and fuel cells.

In order to understand the effectiveness of the various technologies, it is necessary to evaluate issues such as payback periods, seasonal variation, location, as well as local planning requirements.

Our findings showed that whilst renewable energy can provide a cost-effective supply in many circumstances, it needs to be understood that the performance of a particular system will be very dependent on local conditions.

Roof-top wind turbine (Image: PA)
Wind energy is not uniform across the country so these systems are not suitable for every region

For example, too much shade on a solar system will limit the potential output, in the same way that lower average wind speeds could reduce a turbine's efficiency.

Biomass boilers are a good example of a system which offers strong potential for carbon savings. Using wood fuel in the domestic sector holds the promise of being a truly renewable energy - provided the fuel comes from sustainable sources.

Biomass systems can have high levels of efficiency, typically 60%-80% in ranges, pellet stoves, log stoves and log boilers.

But they require careful installation, maintenance, and also require a sufficient amount of space to store the fuel which generally has to be bought in bulk.

In areas that are designated as smokeless zones, some systems will not be suitable, although modern systems generate considerably less smoke than their older counterparts.

When the wind blows

Wind power is often seen as a panacea for renewable energy delivery. However, in the domestic sector, these systems may generate more carbon than they save when the turbines' manufacture and delivery is taken into account.

Aerial view of houses (Image: Science Photo Library)
We are facing some of the toughest tests seen for decades, given these zero-carbon and housing-growth targets

They require uniform wind speeds of 5m/s or more in order to work efficiently, but obstructions such as trees and other buildings can have a significant impact on this.

In addition, wind energy is not uniform across the country so these systems are not suitable for every region.

This means that a site-by-site assessment must be undertaken to discover where their use will gain maximum benefits.

The fact that there is no one-size-fits-all solution is further demonstrated by small-scale hydroelectricity.

Relying on a constant flow of water to generate electricity, the power outputs of these systems will vary seasonally with flow rates.

Also, the cost of installation may be prohibitive when set against the amount of power these generate in certain circumstances.

The capability to generate electricity is increased by the size of the vertical distance the water falls, known as the "head". Greater heads tend to generate more electricity.

Planning issues are significant because it is not always possible to obtain permission.

Testing times

The challenge presented to the housing industry is clear. We are facing some of the toughest tests seen for decades, given these zero-carbon and housing-growth targets that have been set by government.

NHBC has been working closely with government and industry to ensure that the needs of customers are taken into account in the drive to zero-carbon housing.

We welcome the opportunity to work with the new Housing Minister, Caroline Flint, because failing to plan and appropriately implement new measures will be just as bad as doing nothing at all.

We must work hard to deliver on the zero-carbon agenda but without ignoring the realities and issues surrounding the various technologies on offer.

The industry needs time to plan and to manage the implementation of the ambitious 2016 target to ensure that there is a cohesive approach.

It is important that the sector is allowed to make informed choices, based on sound science and safe technologies, backed up by effective testing and accreditation systems.

Imtiaz Farookhi is chief executive of the UK National House Building Council (NHBC)

The Green Room is a series of opinion articles on environmental topics running weekly on the BBC News website

Do you agree with Imtiaz Farookhi? Does the UK housing industry face a tough test to ensure all new homes are "zero carbon" by 2016? Will the inappropriate use of technology be as bad as doing nothing at all? Or is something better than nothing?

I love you guys; still squabbling in the mud over the beans, and unware of the giant with the big stick . . . all of this is fine, provided we STOP where we are. But of we carry on breeding like rabbits; we will trash all of this and be looking around for something more in only a couple of years. There is no more. So you think you can double the efficiency of our houses - then use that as an excuse to build twice as many houses - back to square one again !! And the joke is; you really don't get this do you ?! You guys still think you can "throw a little technology at the cracks, and carry on business as usual" - more people - more stuff - more stuff - more people. Well there is no more "business as usual" we've hit the buffers. Planet Earth is still 24,000 miles round the middle. It's been that way for a billion years, and it's going to stay that way for the next billion years. There is no more planet. It's over ! Now what are going to do next ? - "We cannot risk a situation where one, two, or three generations of consumers will have to live with the legacy of poor decisions made today." - he's right there ! - and the "poor decision" is to try to carry on for those "three more generations of consumers" - and you still don't get the joke - the clue is in the title !! Cheers for the laugh . . . the only probem is; you people seriously believe you can carry on doing this ??! Do you really think the planet will tolerate "three more generations of consumers (of this planet)" The joke is in staring at you in the title and you still don't get it ?!
steven walker, Penzance

Efficiency is more important than renewables. The implementation of climate-change-bandwagon methods like mini wind turbines only benefit the suburban householder's conscience. Renewables technologies have to be chosen using a sensible, business-like approach, using only those that provide a genuine benefit to the environment and the budgets of householders and businesses.
David, Cheshire

The article suggests that wood fuel is a good thing. However, it needs to be remembered that burning wood also produces other greenhouse gases. It is also a danger to health due to particulate and cancer causing organic compound emissions. It is also an insulation problem inasmuch as you need a chimney. I was under the impression that the EU had effectively banned chimneys in new build precisely to improve insulation standards.
Simon Francis, Wolverhampton UK

Yes inappropriate use is a bad plan and I think that there is mis-selling going on of the paybacks and utility of some alt schemes - especially solar power. However, every new house should be provisioned with the means to inject electricity locally and the regulation to allow it - but let local decisions by householders (possibly linked to planning approval and buidling regs) apply the what and how. There are also daft things still within Government legislation that hamper things. I know someone who wants to invest in a small water based power generator on their land - it would take forever to pay back but they are green at heart. However, they would have to pay the water company 'extraction' charges to use the water running down their own land! Madness. Much better focus for the Government is to stick to the knitting in terms of getting the regulation right for local injection and pushing the tech that we already have that, properly used, brings Reduction in usage. It should be a matter of shame not to use a timebased thermostat in your house to take at least a degree or a few off your internal house temperature when you are under a duvet/out at work etc. For a device that just fits what people currently have and costs 25 thats a rapid way to cut your 60% space heating figure. Why doesn't every visiting boiler engineer fit one and train the householder to use it? Large combi-boilers with small heat cubes in them are great too - run a 'kick out your tank' programme many folk will be glad of the space this frees up as well as the gas use reduction - and not a solar cell in sight.
Oliver Anderson, Leeds

The pie chart in this article says it all. If we can address the need for space heating in all new housing, we can make incredible savings. And we already know how to. It's perfectly feasible to build homes that require no additional heating; in the German developed Passive House, the heat generated by normal appliances and the people living there is enough. So a vast improvement on thermal insulation is required. That can address the new build, but we also need to tackle existing housing as well. Again, improving the thermal efficiency is the most cost effective way of doing this. Home renewables certainly have a part to play, particularly solar thermal and ground source heating. Unless you're incredibly lucky where you live, I wouldn't waste your time or money with domestic wind turbines.
Benny, Edinburgh, Scotland

You explain Bio mass, but trees absorb Co2, when the tree is burned it releases the co2 again? Ground sourse heat pumps use the constant heat in the ground an some are more efficient than other COP of 4 You did not cover Ground Source Heat Pumps this is often the case mainly because its not understood, Your fidge freezer does its job the same technology is used in round Source Heat Pumps, they dod there job
Philip Sheldon, Notts

UK gas is in steep decline. How much can gas can Russia supply to Europe to cover the shortfall? Indeed do we want to be that dependent? Retro-fitting existing property to use something other than gas is going to be very painful. If we're going to get serious there needs to be a simple and easy to apply for tax rebate on alternatives.
Darran, West Malling, UK

The UK housing ind. does face a tough test ensuring , , , About the use of inappropriate technology, these are early days' and some technologies may later be found not to be the best for the job but I think that the green movement is finding its footing fast and this is very encouraging, keep up the good work.
R Wilson, Musselburgh, Edinburgh, Scotland.

Farookhi is right that it is a challenge but he names 11 proven alternatives straight up, and fails to mention better insulation as being the most obvious way to save on the 85% of energy used for heating. As with many environmental arguments, better economics would make for simpler choices - keep building cheap houses that are expensive to live in, or pay more up front but save a fortune in living expenses.
Brian, Canberra, Australia

Housing policy should not take place in a vacuum. Significant energy savings requires increasing housing density. Otherwise there is no net energy savings. Heat pump water heaters that use air exist now. Same is true for space heating. Problem is that capital cost may not justify energy savings. Heat pumps and central power production is much better than concepts like micro generation. Micro generation is a load-matching nightmare. Use may require drying hair in the shower. Once central generation is chosen over distributed energy, then housing CO2 emmissions can be reduced to zero. Only issue is how to produce central power. Solar, nuclear, wind, tidal, coal with sequesterization are all put on a equal playing field. Political problem with is that nukes easily win. Existing nukes and existing coal plants are the cheapest power producers. Result is unacceptable to very-far-left because capitalism does not die.
William Ernest Schenewerk, Los Angeles USA

The whole article talks about getting renewable energy out of the environment. But everybody should known that the most economical and environmental method is not wasting energy in the first place. The biggest energy consumer (60% in the pie chart) is heating thus we should first isolate houses. We need to build airtight houses with a controlled ventilation system which recuperates the energy from the outgoing air. Compared with a K60 house, a four times better isolated house (K15) uses only 10% of the energy for heating. This is due to the "free" energy from cooking, electric devices, sun coming through windows and the people living in the house . Only AFTER good isolation can alternative energies help to reduce the fossil energy requirements to zero. The article does not mention the word isolation a single time. The priorities of the article are not correct. Better isolation does not only improve carbon emissions, but also comfort. Please lookup passive house on any search engine for more information. With current energy prices it is still a challenge to make it cost effective in a short period, but if the cost of energy rises further, it is the best way to save you troubles in the future. Energy efficiency (isolation) and most renewable energies allows you to known how much you spend for how much energy you save. Doing nothing makes you vulnerable to the unpredictable energy market. Best regards Marc
Marc De Decker, Nossegem/Belgium

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