At work I’m helping a large housing association upgrade their existing heating networks to save carbon and reduce costs to occupants. There are various steps to take: upgrading boilers, re-insulating distribution pipework, considering CHP, and so on. But the single most effective thing you can do on these schemes is to install heat meters.

Doing some background research, I rang up the very friendly and forthcoming Dick Bradford, the driving force behind the hugely successful biomass community heating schemes in Barnsley, to ask him what effect installing heat meters had had on his schemes. He told me that following the installation of heat meters, heat consumption dropped by 50%. I was gobsmacked.

But when you think about it, figures like this aren’t crazy as they first appear. Because typically on these old schemes the occupants pay for their heating via a fixed standing charge. This disconnect between consumption and payment has predictable consequences: people leave the heating on 24/7 and regulate the temperature by opening windows. If you’re suddenly required to pay for what you use, you’ll use a hell of a lot less.

The savings Dick spoke about were much higher than BRE reckoned in their recent Desk Study on Heat Metering(pdf), but if you read that report you’ll see that the BRE were using the finger-in-the-air index to arrive at their figures. They didn’t have any firm results on the likely savings from heat metering and suggested that 30% was the upper bound for social housing.

If Dick is right, then I reckon that’s a 35% drop in total emissions from each flat, just from installing a £200 bit of kit and spending maybe £50 - £60 a year for operation, billing, and replacement. Compared to the alternatives this is very high carbon savings per pound spent (to get an idea, take a look at the cost figures in table 2.1 in the recent BERR Call for Heat Evidence).

Regarding O&M and billing, there’s an important point here: there’s a whole lot of existing community heating schemes out there (BRE reckon 1-2% of all housing is on a heat network) with 75% of supplies unmetered. If you install heat meters, suddenly someone has to manage the meter reading, billing, debt chasing, etc. That’s quite a headache for a local authority or housing association if they’re not geared up for it and I suspect this is the factor that stops many organisations from moving to billing for metered supplies.

To address this issue on my current project, we’re proposing to hand over responsibility for meter reading, billing, etc. to our not-for-profit ESCO, Fonten Power. Margins are minimised, energy costs to occupants kept low, and the client avoids the expense of developing the capability in house. We still need to flesh out the details but I’m confident we can arrive at a very cost effective means of saving a whole lot of carbon - and save tenants money on their bills at the same time. I’ll post progress here.