With well-insulated houses and central heating as standard, I always grew up with heating the space as how you stay warm in the winter. A colleague once shared with me that where he'd lived, they thought of it as heating people, not spaces when looking to stay warm.

The heating people approach means rather than heating the air in the room, you focus on heating the person: warm clothes, hot drinks, baths, cosy furniture with high backs and sides that traps heat in, or furniture that is itself heated like the kotatsu or aga, and generally local heating where a small room or even part of a room may be warm while the rest may be cool — dividing screens are sometimes used.

This approach was common until relatively recently and also still is in countries where it was difficult to stay cool in the summer and houses weren't typically built to keep heat in.

Thanks to Peter Wyatt-Brandenburg for sharing with me many years ago.

Heating people, heating spaces

A rather clever way of capturing energy as vehicles slow down is to store the energy you'd use in braking as gravitational energy. This way of storing energy is used on a number of central London underground stations by constructing the stations at the top of a small hill in the track. Once built, the hump-back-station design has the handy effect of naturally slowing trains down as they approach a station and naturally accelerating them as they leave a station. Apparently, on London's Victoria line this saves 5% in energy and helps the trains run 9% faster.

You're not always going to be able to put a slope just where you need to slow down, unfortunately. However, it makes a ton of sense for pedestrian crossings where raising the crossing to the level of the payment means pedestrians don't have kerbs to negotiate and cars are naturally encouraged to slow down.

Victoria line data from Sustainable Energy without the Hot Air, by the late David JC MacKay

Hump-back stations

I've been there. I'm holding some packaging that kind of looks like it ought to be recyclable but isn't one of the standard products that are asked for. I could put it in the bin and then it'll head straight to landfill, or I could put it in the recycling and then it has a chance of being recycled, right? So it often seems better to recycle it in the hope that it might be recovered rather than consign it to certain landfill. This is known as wishcycling.

Sadly, from all that I've read about wishcycling it's not the best approach. When we put in non-recyclables into a recycling bin it contaminates the high quality recyclable materials and several things can happen:

A lot of dry recycling is still manually sorted in Materials Recovery Facilities (MRFs). When the quality of the input goes down it can require more people to sort it. It's not a pretty job if it also contains items that are contaminated with food waste

Non-recyclable items that processing machines aren't designed for can damage them and mean costly maintenance

Items like batteries that make it into regular recycling can start fires in paper bales which is dangerous and expensive

Non-recyclables mixed in can mean a lower quality end product to use to turn into new products. This can reduce what it can be used for and make it harder to sell

Paying more pickers and sorters and servicing machines costs money, and selling lower quality products brings less in, both of which reduce the profitability and potential viability of recycling operations

So the advice I have learned to take on board is:

Counterintuitively, if we want to recycle more, it seems at the moment we have to recycle less.

And even better is to reduce and reuse where possible in the first place.

Wishcycling

An average car, sat idling, can produce exhaust emissions to fill 150 balloons. That's a lot of balloons to imagine puffing away out of the cars idling outside a school for a pickup, say. Other tests have found (pdf) that for any time over 10s fuel use and emissions are always greater when idling than turning off the engine and restarting. Spread the word.

Of course, if you have an electric car this won't apply.

I did draw 150 balloons, but a few of them didn't fit on the page.

Idling

Life on a nuclear submarine is life under some pretty intense constraints. For one, there’s not naturally any fresh water and any time you use it the waste water builds up in the tanks and then has to be expelled, and when you expel it that makes noise, and because nuclear subs don’t want to give away their location they do their best to minimise the number of times they have to do that. That means taking care of all fresh water.

The other reason to take care of fresh water usage is that they have to make it the whole time — any fresh water for cooking, cleaning or drinking has to be made from sea water. If you drink a glass of water on a nuclear submarine you’re probably drinking the most expensive glass of water you’ll ever drink because it’s been desalinated by a nuclear submarine.

Hence the submarine shower with a total of 20 seconds of water: 10s with the water on, turn it off while you soap and scrub and finish with 10s of rinsing. That’s it. For me it’s a nice reframe in how much you actually need when you take a shower, and it still works. So if you fancy saving water and energy you could give it a try.

Submarine shower

Perhaps the most important curve of our times, Charles Keeling’s  curve shows the change in concentration of CO2 in the air with measurements taken every year for over 60 years. Taken at the top of Mauna Loa volcano in Hawaii because of its high altitude and relative isolation in the Pacific, Charles Keeling’s measurements show that the monthly average CO2 concentration in the air has risen from around 310 ppm (parts per million) to around 410 ppm in 2020. As a greenhouse gas this change in CO2 concentration is one of the critical causes of climate change.

The concentration varies seasonally as plants bloom in Spring and Summer reducing the concentration from its high around May as the CO2 has built up over the Norhern Hemisphere Winter.

The Scripps CO2 program is now overseen by Charles’ son Ralph Keeling.

The Keeling curve

If you lived on Easter Island, would you really cut down the last mighty tree knowing that would be it? It seems either foolhardy or desperate to knowingly cut down the last of a kind and your last source of timber. So how could it happen?

Jared Diamond, in his book Collapse and article Easter’s End, explains how this situation could happen through a gradual, hardly noticeable decline over many years. Those who remembered the great trees which they used to make rafts, canoes and ships were old or had long since died. The trees seen today may be nothing like the forests and towering trunks of tens or hundreds of years ago.

Gradually trees became fewer, smaller, and less important. By the time the last fruit-bearing adult palm tree was cut, palms had long since ceased to be of economic significance. That left only smaller and smaller palm saplings to clear each year, along with other bushes and treelets. No one would have noticed the felling of the last small palm.

For another perspective, Seth Godin asks who cut down the second-to-last-tree?

Who cut down the last tree?

Astronauts returning from space have repeatedly shared experiences like this:

“You develop an instant global consciousness, a people orientation, an intense dissatisfaction with the state of the world, and a compulsion to do something about it. From out there on the moon, international politics look so petty.”— Edgar Mitchell, Apollo 14 astronaut

“When we look down at the earth from space, we see this amazing, indescribably beautiful planet. It looks like a living, breathing organism. But it also, at the same time, looks extremely fragile … Anybody else who’s ever gone to space says the same thing because it really is striking and it’s really sobering to see this paper-thin layer and to realize that that little paper-thin layer is all that protects every living thing on Earth from death, basically. From the harshness of space.”— Shuttle/ISS astronaut Ron Garan

The overview effect, coined by Frank White, is kind of the mother of seeing the forest for the trees. It’s the realisation that we live on a fragile planet, we are all connected, and this is all we’ve got.

The sketch is based on the image of earth from the moon taken on the Apollo 11 mission.

The overview effect

Back in 1865, a chap called William Stanley Jevons noted that while there had been a number of improvements in coal efficiency in steam engines and the like, instead of reducing consumption the effect was to increase consumption instead — Jevon's paradox.

While it’s not a surefire outcome, there are plenty of parallels like more efficient batteries leading to more overall battery use, washing machines leading to doing more washes rather than less time spent washing, or the ability to recycle some plastics leading to more overall plastic consumption.

This is sometimes known as the rebound effect.

Also see the fifth fuel: energy efficiency, and save some landfill.

Jevon’s Paradox

In his 4 min TED talk, Kamal Meattle explains how to grow your own fresh air inside with just 3 common house plants. The areca palm works hard in the day, mother-in-law’s tongue during the night, and the money plant cleans out volatile chemicals. He transformed the air inside a New Delhi office park by filling it with these 3 plants to some wonderful health and productivity benefits. You could do much worse than add a few of these to your office.

How to grow your own fresh air

The Fifth Fuel: energy efficiency

From Michael Braungart and William McDonough’s groundbreaking book Cradle to Cradle (you should buy it just to feel the book itself). Production and use need not be a straight line. It has to be a loop.

Think cradle to cradle

If a baby wore 2 reusable nappies per day, that’s nearly 1500 nappies saved from landfill by the time a child is 2 years old. If every baby born in the UK did this, that’s 2.5 Big Ben’s worth saved from landfill.

Save some landfill with reusable nappies/diapers

Learned from Joe Smith’s short entertaining TED talk: How to use a paper towel.

Sketchplanations tagged with sustainability