National Security Eggs

(Photo from A Global History of Food)

The average house built in the UK is among the smallest in Europe, with some of the worst energy performance. Along comes an energy crunch and what does the government want to do? Build another nuclear power plant!

It takes ten to twenty years to do that, costs a fortune, generates toxic waste with such a long half-life that it will still be radioactive when we’re long extinct, and (as we’ve seen in Ukraine) is a big fat target if an enemy wants to cripple a huge swathe of a country with a single action. Japan has shown us that Mother Nature can wallop a nuclear power plant, too.

When people set up solar power and microwind generation at their houses, the installers sell those systems by talking up the impact on their household utility bills. For many people, that’s more appealing than the environmental benefit of getting electricity without burning fossil fuels.

For some reason, nobody mentions that it’s a household contribution to national security.

Centralized Power Generation as a Vulnerability

If a town gets its power from a central power plant, even a conventional one, anything that takes down the power plant leaves the whole town in the dark and cold. But if a town’s power generation is spread around on many rooftops and small, quiet microwind turbines, its power isn’t vulnerable to a single failure (or military strike) anywhere.

Centralized power generation of any type puts a lot of national security eggs in one basket. Until recent decades, we had to tolerate that vulnerability because it wasn’t practical for most homes to generate their own electricity. Now it is practical for many homes to generate at least some of the power they use. We can spread these national security eggs around as a bonus for doing something that is beneficial to our own budgets and to the world’s climate.

But we could do even better.

Housing Conventions

Our house is a conventional UK modern build. Our new solar power system and the microwind turbine we will add this autumn will produce a large proportion of the energy we use, but we’re not likely to become completely energy independent. For heating alone, the average modern British house uses about 150 kWh of energy per square meter per year. Older houses are worse, using about 200, and leaky ones use about 300.

Low Energy houses use 50. Houses build to Passivhaus standards use 15.

If we built new housing to Passivhaus standards, our energy needs for heating would be 10% of what they are for conventional modern houses. A solar-and-microwind system like what is being added to our house would provide more power than we need even if we actually kept our house warm in winter instead of only the living room. We would be able to supplement the distribution grid substantially, to the benefit of the community.

Why Not Build for Energy Efficiency?

Housing built to Low Energy or Passivhaus standards is amenable to methods such as factory built with assembly on site, and the houses go up in days rather than weeks or months. This makes more efficient use of materials and labor than site-built housing, a counterbalance to much of the cost of building to a higher energy efficiency standard.

We know better than to look at issues like this in isolation. As soon as we ask why British houses are still being built for poor energy efficiency, we get into other areas. But first let’s take a closer look at how most houses are built here.

Most modern houses in the UK are built with a brick exterior, an air gap of a couple of inches (which the home buyer may later get filled with some type of blow-in insulation), a layer of foam insulation board, concrete block walls (including some interior walls of half-thickness concrete block, which may or may not be load bearing), then plasterboard stuck on with thick daubs of adhesive. This convention uses immense amounts of material, requires a lot of labor, takes a lot of time, and generates a large carbon footprint. The resulting house is a lump of thermal mass with poor insulation.

Going all the way to Passivhaus standards would result in a house that costs about 10% to 11% more to build than a conventional house. That’s about £26k on the (March 2021) average house price of £256k. The energy price cap is expected to rise again soon, to £3800/year or about 3x what it was a year ago. If you could have a house that uses 10% as much energy as a conventional house, in theory your energy bill would be £3420 lower than the average. At that pace, energy savings would overtake the extra cost of building the house in less than 8 years… years in which you would be more comfortable than in a standard house. Your extra cost would be part of your mortgage at a lower interest rate than financing for retrofits to try to improve the energy performance of an ordinary house, and payments would spread out across more time.

Standard practice for housing developers is to build a house, then price it at a specific percentage above the cost of building it so that the profit margin will be a specific percentage. The higher the cost of building a house, the more money the profit percentage will turn out to be.

We would expect the builders to switch their methods so they could charge a premium for Passivhaus energy performance and get more profit… but there are complicating factors. Remember that factory built, site assembled housing uses less labor. Government programs encourage creation of more jobs. The construction industry is a favorite sector in which to boost jobs and apprenticeships, and it donates heavily to (and heavily lobbies) political interests.

On top of that, builders don’t want to build houses more quickly. Not having enough housing to meet demand pushes prices up and boosts the housing developers’ profits. If they develop housing at the pace of factory built, site assembled methods, housing supply could get closer to demand, softening the rate of price rises.

So Here We Are

We end up with houses that are expensive to operate for less comfort than what we could have with better energy efficiency. We end up with centralized energy infrastructure that is expensive to build and run, vulnerable to having hundreds or even thousands of buildings without power when something goes wrong with centralized power generation.

It isn’t good for our personal finances, our comfort, the environment, or national security. Government policies push to continue going in this direction, at least in the UK. We are switching some of our electricity generation to wind, and that’s a huge step in the right direction, but we still have a bias to do everything in a centralized way with big infrastructure. We make vast wind farms (for Britain, mostly offshore) with towering turbines.

Widely distributed power generation on a small scale supplemented by big infrastructure would put fewer national security eggs in big baskets, and scatter more of the eggs so that a single large event couldn’t take them all out.

Policies aren’t necessarily rational, and the way they interplay can easily be this nutty. It would be a dream scenario for enough people to find a way to do their bit about this and leave policy makers scrambling to catch up. But it wouldn’t be only the economists and politicians scrambling. It would also be national defense… probably with a sigh of relief.