Divide and conquer

20th century tech for a 21st century world

Our electricity infrastructure was once our society’s greatest asset. It brought light where there was darkness, heat where there was cold, and motion where there was stillness. It powered our entire economy, and still does. However, it has become a liability.

Like the baby boomers, it grew up in a different era. At that time massive, centralized bureaucratic organizations were the norm. Fuel was cheap. Much of it came from domestic sources. The primary threats to security were the nuclear arsenals and massive armies of NATO and the Warsaw Pact.

The electricity production, transmission, and distribution reflected that society. Electricity was produced in massive, centralized facilities. The principal fuel sources were oil, coal and uranium. Little of that was imported.

That world is gone. While massive organizations still exist, the engine of economic innovation is small business. Increasingly, individuals are free agents, contracting their services out to the highest bidder and resisting the allure of “going corporate”. More and more people work out of their homes instead of commuting to an office.

At the same time, fuel has become more and more expensive. Partly because of steadily increasing demand, and partly because of declining domestic reserves, much comes from overseas.

The cold war is long over, and few now worry that our world will end in an all-out nuclear war followed by nuclear winter. Instead, the prevailing security concern is terrorism. Since 9/11, our entire society has reworked itself to defend against an enemy that is not on the other side of the globe, but potentially next door. Critical infrastructure assets are protected in a way they never were in the last century.

Because of our legacy electricity infrastructure, we remain vulnerable. Nuclear power plants present a tempting terrorist target. A successful strike on one of these would not just release radioactive material into the environment, it would also leave a gaping hole in regional generation capacity. This could lead to rolling blackouts and economic chaos while the utility fought to restore the lost capacity.

A hydroelectric dam is similar. These massive structures would be difficult to destroy, but not impossible. The instantaneous release of all the water stored in the reservoir would cause a wave of destruction worthy of a Hollywood disaster flick. The loss of the generation capacity would have a similar impact to that of our hypothetical strike on a nuclear plant.

Less consequential, hence less well-defended, and hence more vulnerable, are thermal plants like coal-fired generating stations. A successful terrorist strike would be unlikely to inflict physical destruction on the surrounding area, at least not on anything approaching the scale of a nuke plant strike or a dam burst. However, it would cause comparable economic damage.

With the advent of renewable energy technologies like wind and solar, the logic behind large-scale, centralized generation facilities has been largely eliminated. Wind and sun are everywhere. In spite of that, wind and solar developers have persisted in perpetuating the centralized model. Large wind farms, with turbines covering a huge area, are commonplace. Ditto large solar farms. Like the coal-fired generating station example, these facilities are vulnerable to terrorist attack. What’s more, they fail to address one of the largest challenges to renewable energy – its transience.

The wind doesn’t always blow, and the sun doesn’t always shine. However, if generating capacity is spread out instead of concentrated, it spreads out the risk. The sun may not be shining here, but it probably is somewhere else. Today may not be windy there, but it is here. On average, the risk of cloudy skies and feeble breezes is mitigated, but only if solar arrays and wind turbines aren’t all in one place.

Big wind and solar farms are not the way to go. They are vulnerable to terrorist attack – albeit with little or no knock-on effects to the surrounding area. They fail to mitigate the risk of variable sun and wind. What’s more, they necessitate upgrades to transmission infrastructure in remote locations – a costly and unattractive proposition – and because they are remote, an appreciable amount of their electricity is lost as heat as it passes through transmission lines on the way to market.

Far better to site generation facilities close to the point of use. Solar panels are a natural fit for many buildings. Parking lots are an ideal location for large dual-axis trackers, and offer the added bonus of potentially being coupled with charging stations to supply power for electric vehicles. Even wind turbines – the vertical axis variety – are perfect for mounting on rooftops of tall buildings, where winds are high, birds are few, and what little noise there is will go unheeded.

Thermal plants also offer significant potential for distributed generation. Legacy thermal generation facilities are grossly inefficient, as they produce a phenomenal amount of waste heat. If the plant were located in an industrial park or a high-density housing development, the heat would no longer be wasted – instead, it could warm all of the buildings in the area through a district heating system.

As for a fuel source, the best-established choice is natural gas. The price of this fuel has dropped precipitously of late with the advent of shale gas. It has the added bonus that it can be replaced or supplemented by renewable biogas produced by running organic waste (sewage, compost) through an anaerobic digester. It could also burn hydrogen. A gas turbine would produce both electricity and heat.

Another option would be, believe it or not, nuclear. Traditional uranium-fuelled reactors are a non-starter, because nobody would want them in their neighbourhood, and they’re much too large anyway. However, a Molten Salt Reactor (MSR) fuelled by thorium could, in theory, be built small enough to supply combined heat and power to a neighbourhood. The high-grade heat from the reactor spins a turbine for electricity, and the low-grade leftover heat supplies the district heating system.

It’s time our utilities ditch their mindset that bigger is better. Big generation facilities are big targets. Big wind and solar farms are big risks for when the sun don’t shine and the wind don’t blow. And big heat means big waste.

Power generation needs to be small. And it needs to be everywhere. It eliminates targets, reduces risk, and gives more bang for our buck.