SprintBio zero-carbon homes - Distibutors of environmentally friendly boilers, burners and heat pumps

Spain has recently announced a significant move towards the use of domestic solar water heaters in a bid to improve self-sufficiency and lower rising household bills. The goal is eventually to emulate Israel’s domestic water heating situation where 90% of homes are equipped with such heating systems, meaning that hot water supply has near zero financial and environmental cost. But such countries obviously have quite an advantage over the UK in the solar energy stakes, and alternative solutions must be sought if the UK is to achieve something similar.

It is not that solar heaters are unavailable in the UK - they are - and can provide a significant portion of a household’s water heating energy needs, especially in areas of Southern England. But whichever way you look at it the numbers just can’t match those of Israel and Spain in terms of broadness and scope of viability. Solar water heating has a part to play, but so too must alternative solutions…

The two aspects of approaching the problem involve reducing the amount of water required from a mains supply, and secondly reducing the amount of energy (again from the mains supply) that is required to heat this water.

In order to tackle the initial issue there is a highly viable solution available for UK homes; rainwater harvesting. Such water can be collected either from a large surface such as a building’s roof or from a large ground area, and can be used for flushing toilets, watering gardens or even supplying the washing machine.

With average daily water use in the UK currently at 150 litres per person, rainwater harvesting has a significant part to play in reducing our dependence on mains supplies (not to mention household bills, especially considering the imminent water price increases scheduled for 2010).

The second issue, of water heating, has multiple solutions and should be assessed on an individual basis depending on particulars of location and weather of your area, but the main options involve the aforementioned solar panel systems, to biomass boilers as well as ground and air source heat pumps (more information on these technologies can be found on the ‘case study’ section of this page).

The bottom line is that such technologies will not be suited to installation in all UK homes, but also that at the same time there are many that would benefit financially (in terms of reduced household bills) by adopting such tools, especially in the current climate of rising household bills. Perhaps it is time such moves were no longer considered a shopping or home improvement choice, but rather incorporated into a government housing intiative to inform those who could benefit about what is available and how such changes can be implemented.

The collective environmental benefits would encompass helping meet housing goals of reducing the average UK household’s carbon footprint, with obvious environmental benefits for all, as well as being a more short term crisis solution with regard to the current cash squeeze and climate of rising costs.

Dejan Levi

Under current UK government legislation all new-build homes must be zero-carbon after 2016. However, some of the major builders are trying to get a head-start on this deadline and have begun developing designs and prototypes already.

One such company is Barratt Developments - one of the UK’s largest firms - which this week unveiled designs for what will become the country’s first zero-carbon house built by a volume builder. The first examples of these homes will be available from 2011, in a 200 unit batch at the site of Hanham Hall hospital, near to Bristol.

All of this sounds great, except for one snag - the cost of the homes. Though Barratt have not specified the exact value, their chief executive, Mark Clare, has said that it will be ‘difficult to reduce the cost of the current prototype to commercial levels’.

Now, it’s all very well having lots of zero-carbon homes, but not so great if they all lie empty because nobody can afford to buy one… The question is; what can be done to avoid this situation from developing?

Well the simple fact is that such projects will require quite a degree of government assistance to succeed quickly. No doubt Barratt and other developers will do what they can do drive building costs down - but ultimately there is only so far this can be taken before we are left with a zero-carbon, but ugly and low quality home that nobody wants to live in.

In the first few years after 2016 (maybe even before) it will be crucial that the government subsidises the cost of such homes so that they can compete with the older properties on the market. Some measures have already been introduced, such as a stamp duty waiver until 2012 on zero-carbon homes worth over £500,000 (homes under that value are eligible for a £15,000 stamp duty discount).

This is a start - but hopefully only the beginning of a series of similar moves.

Barratt’s prototype for example utilises solar panels, rain-water harvesting, and an air source heat pump. It is these features, along with its super-insulation and triple-glazed windows, that have earned it the best possible energy use rating of grade 6 (signifying a completely zero-carbon home). Perhaps the industry sectors producing this technology could do with a few tax cuts, or incentives in return for helping reduce costs.

It is true that a zero-carbon home will face only very minimal running costs and hence a case for the higher asking price could be made on these grounds. The problem is that, if would-be buyers cannot even secure a mortgage for the house, the rest becomes irrelevant.

This is where banks have a part to play - by introducing a different mortgage option for buyers purchasing such homes they could be instrumental in the success of zero-carbon housing. With the current credit problems many banks have reigned in their mortgage options of late - but those buying a zero-carbon home in the future will have a greater ability to repay a big mortgage - due to the lack of gas and electricity bills. A bigger loan could therefore be repaid in the same time as a smaller one on a non grade 6 property.

There are many other potential measures currently being discussed - but the main point is that the government needs to seriously consider further legislation (or funding for buyer-assistance schemes) in order to ensure that the initial mandate of zero-carbon by 2016 is the success it has the potential to be. If this can be effectively managed then the (positive) consequences could be far reaching indeed - from the inherent environmental benefits, to reducing the cost (while raising the standard) of living in the UK. Let’s hope those involved can get it right, for we all stand to reap the rewards of this effort.

(A detailed image of Barratt’s design can be found here).

Dejan Levi

An article from The Guardian about a commercially viable, affordable and ready to purchase zero-carbon home. The houses use a flat-pack timber-frame kit based on the concept of the timber-framed houses that were built in Britain about 1,000 years ago.

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