The Heat is On

19 Oct 2015 | David Casale

Apart from being one of Gloria Gaynor’s better known hits, it also signifies that, as of today (Friday 15 October), the heat in our home will be on. Many of you will have had your heat on since the cold snap in September or so National Grid tells us from daily demand for gas. This evening, my wife will raise a glass to the start of our heating season, picked to match the Soviet Union (more of that later…).

To quote Ed Davey (who? Energy Minister in 2014):
‘… there has been a historic failure to get to grips with one enormous part of the energy jigsaw; the supply of low carbon heat… We have, however, inherited a big hole where there should be policy for finding alternatives to fossil fuel for the supply of heat. In a country like ours, and for obvious reasons, we require a lot of heat: a consequence of our geography, our housing stock and the scale of our industrial activity. As a country, we spend £32 billion a year on heating. It accounts for around a third of our greenhouse gas emissions. Without changing the way we produce and consume heat, we will not meet our long-term climate change target. To get there, we are going to have to change the way we generate, distribute and use heat in buildings and industry. And we are going to need those changes to take place in an orderly, cost-effective way that ensures a vibrant, low carbon economy and a supply of affordable energy for all consumers.’

Very well said, sir!
Now how are we going to do that? This was a topic for debate at yesterday’s Energy Research Partnership (ERP) event in London. There are currently three runners and riders and each has strong benefits but equally significant challenges:

  • Air source heat pumps
  • District heat networks
  • Hydrogen economy.

These are three exciting prospects if you are, as I am, an engineer who likes to help fund innovative companies. However, they are going to be very expensive, take a great deal of planning, need talented people from a wide range of disciplines and take a decade or two to deliver.

Air source heat pumps
Let’s just say heat pumps in any form, as they can also work on sunshine, river water and Earth amongst other heat sources. These devices are measured on a coefficient of performance of around 2.5 to 3.0 (so three units of heat out for each unit of power in). They are not totally decarbonised as the input power usually comes from the grid. They have the advantage of being hung on the side of houses but that creates issues for blocks of flats. There is also a concern about noise and a question as to whether in the depths of winter they can produce enough heat for our leaky homes…

District heat networks
90% of the former Soviet Union uses surplus heat from power generation to fuel a massive hot water distribution system for domestic heating. These systems are normally activated on 15 October each year. However, in terms of applicability elsewhere, consider the well-known joke about a tourist in Ireland who asks one of the locals for directions to Dublin. The Irishman replies: ‘Well sir, if I were you, I wouldn’t start from here’. Soviet cities are designed around their heat systems, whereas we will need to design our heat systems around our cities. Where we build new towns there is an obvious opportunity, one that we are only partly taking up.

Hydrogen economy
OK, I would not have included this in my list before attending the excellent ERP workshop. Hydrogen could be the answer, if for no other reason than it can be done. As you will have seen from walking down the road, we are replacing all of our low pressure cast iron gas mains with bright yellow plastic pipes. It turns out that these pipes can carry H2, so we can supply slightly modified boilers that run on natural gas or hydrogen. All we need is a lot of H2 and a good PR department. If that sounds far-fetched, remember that, 60 years ago, Town Gas was 52% hydrogen. I for one will be getting up to speed on low cost hydrogen production; essentially it’s power and water which doesn’t sound too bad …

So, next time you place your hand on a warm radiator, ask yourself:

  • Should this be on? (If it’s past 15 October, when the Soviets turn the heat on, then you’re ok)
  • How will we do this in 2050?

Enjoy the heating season!

David Casale