Tuesday, September 18, 2012

Getting all the parts right

My brother is just going to love this story.  And he has dozens of similar examples to demonstrate that the kind of problem outlined below is certainly not limited to the British Isles.  At least once a week, he gets called to inspect a home with expensive new windows that have not produced the expected energy savings.  Then he gets to tell the poor homeowner that energy efficiency is the sum of many parts and the difference between cheap and expensive windows is a pretty trivial part.  In other words, they just blew a lot of money for a "cure" that doesn't cure much.

I have been following the Swedish homebuilding industry since the early 1980s and even back them, their skills and techniques were probably the best in the world.  The key to understanding their approach is they make houses as absolutely airtight as possible and then manage the necessary ventilation functions with carefully engineered air exchange equipment.  Constructing a weather-tight home and then getting it to breathe properly is a lot harder than it looks—and it looks damn difficult.

In the process of building these super-insulated homes, the Swedes have spun off small industries like NIBE that make the parts to enable super-insulation.  Naturally, these industries want to grow beyond the borders of Sweden / Scandinavia.  Problem here is, a part designed to work in a well engineered super-insulated home is forced to operate in a limp-down mode when the structure is badly-insulated or leaks air where it should not.  In a super-insulated home that performs as planned, the heat recovery systems by NIBE probably work magnificently.  But as can be seen below, GB builders still have to make serious improvements in technique before they're ready for such sophisticated heat recovery systems.  One of the signs that the builders believed they were better than they really are, many of the NIBE units were undersized.

What a freaking mess.  And yet one more example that it takes more than good intentions to build green homes.

Families facing £2,000 bills for green heating 'that does not work in Britain'

Some families in 'affordable homes' said their electricity bills last winter were so high they had to choose between heating and eating
By NICK CRAVEN 15 September 2012

Millions of pounds of public money have been spent installing a ‘green’ central heating system that residents claim doesn’t work properly – and that has made their heating bills four times higher than expected.

Annual running costs had been estimated at £500, but instead some housing association tenants have been saddled with bills of up to £2,000 a year – nearly twice the UK average.

Some families in ‘affordable homes’ said their electricity bills last winter were so high that they had to choose between heating and eating.

Cold comfort: Samantha Claussen, who struggled to pay her heating bills, with two of her children.

The so-called exhaust air system works by sucking heat from waste air leaving the house and pumping it back in to provide heating and hot water.

But if it does not raise the boiler water temperature enough, an electric immersion heater kicks in, sending bills rocketing.

Government grants were spent on the all-electric Swedish NIBE systems but experts say they are wrong for most British homes, which are not as well insulated as those in Sweden.

Heating expert Geoff Morgan, of Rodney Environmental Consultants, has inspected homes in the UK with NIBE heating and said: ‘In Sweden, very little heat escapes through walls, doors and windows, so more is available to be pumped back in.

‘These systems are just not very suitable for your average British home when mains gas is available – it’s just not going to be economical.’

One housing association in St Neots, Cambridgeshire, is considering legal action after claiming that it was ‘mis-sold’ the systems, which cost about £6,000 each.

To be eligible for public money for new housing from the Government's Homes and Community Agency, housebuilders have to follow its Code for Sustainable Homes, which urges low-carbon solutions.

Another in Runcorn, Cheshire, recently spent £145,000 ripping out 69 NIBE sets and replacing them with gas boilers.

To be eligible for public money for new housing from the Government’s Homes and Community Agency, housebuilders have to follow its Code for Sustainable Homes, which urges low-carbon solutions. But residents have reported problems on at least 15 estates from East Anglia to Orkney, and various Facebook sites have been set up by disgruntled householders.

Mother-of-four Sam Claussen said she and her partner Jeff were excited in May 2010 when they moved into a three-bedroom house in St Neots, on an estate owned by the Bedfordshire Pilgrims Housing Association (BPHA).

'Our choice was between eating or keeping warm'

‘I loved the idea of having this modern and green heating system which we were told was going to give us really low bills,’ said Ms Claussen, 40. Indeed, Energy Performance Certificates issued on the new properties estimated annual electricity costs for heating and water at between £400 and £500.

But after living in the property for two months, Ms Claussen was shocked to receive an electricity bill for £252. Costs continued to mount for Ms Claussen and her neighbours on the Loves Farm Estate, and eventually the BPHA stepped in to help meet tenants’ bills – to the tune of £45,000.

By last Christmas, the Claussen family had unpaid bills of £1,500 and were on a key meter.

They found that during a cold snap they were having to spend £10 a day. ‘With such a high electricity bill, we had to choose between eating or keeping the house warm,’ Ms Claussen said. ‘The children were fed, but I hardly ate at all. It was an awful Christmas.’

A spokesman for the BPHA said the NIBE system was recommended by the contractor, Kier Homes, to comply with the Government’s green code.

‘We had representations from NIBE and as a result we were convinced that it was a very good solution. Unfortunately that has not been our experience. Some residents have reported excessive bills, and also there wasn’t enough hot water for their needs.

‘We are currently replacing 43 of the systems with gas boilers. We are also taking legal advice on the next step forward.’

Kier admitted that some NIBE systems were found to be undersized and that some houses had two wall vents rather than one, which meant more heat was escaping.

The company has agreed to underwrite the cost of replacing undersized units with gas boilers, replacing all vents and contributing towards a hardship fund for residents.

A statement added: ‘Since the issues with the NIBE system came to light, we have stopped specifying the boilers.’

NIBE managing director Phil Hurley said: ‘These systems are working brilliantly in thousands of homes across the UK without increased energy costs and, according to independent research, have dramatically reduced costs in many cases.

‘Where costs are high, the issue isn’t with the system, it’s with the way it has been installed or is being used.’ more

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