The Tube is Heating up While London is Trying to Stay Cool

London’s tube system is literally heating up the city – and that’s a problem. A hundred years ago their subway stations were places to cool down during hot summer days and people had to wear sweaters while commuting. Today, this is no longer the case. The trains are heating the earth which in turn makes the entire tube too hot.

Cooling the tube is now a pressing issue and nifty ideas are being tried. New systems being tested tend to be green and benefit other parts of the city. Basically they are trying to transfer the heat to places that want it to save costs.

An experiment in Islington is trying that very thing using heat from the tube tunnels to warm up a municipal heating service provided to a housing estate. The advantage of this scheme is that it can remove heat in winter when it’s needed above ground. It may seem mildly annoying that surface users don’t want heat in summer when you’d think the tunnels are at their most oppressive, but in fact removing heat in winter helps during the summer.

If the clay surrounding the tunnel can be cooled in winter, it has more capacity to absorb heat in the summer.

As it happens, at this particular trial, the fans can also be reversed so that during the summer months, they can suck cool night time air down into the tunnels as well.

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Algae Used for Carbon Capture at Cement Plant

industry

Every year cement production contributes about 5% of the global emissions generated by humans. Any improvement around cement production will have a good impact on lowering carbon entering our atmosphere. In Sweden there’s one company using algae to lower its emissions. The country has carbon emission rates that are likely increasing in the next few years, which has inspired the cement company to figure out how to avoid paying more for producing the same amount of cement. Their solution: pumping the carbon output from their cement factory onto algae which then inhales all that delicious carbon, once the algae dies it becomes food.

It’s elegant: Take water from the Baltic Sea’s Kalmar Strait next to the plant, pump it about 100 meters (330 feet, about the length of a soccer field) into bags that can hold about 3,000 liters (800 gallons) of liquid. Add key nutrients to multiply the naturally occurring algae, and then let them soak in the gases piped to it from the cement plant (what would otherwise be the factory’s waste product) while the sun shines.

What’s more is the algae are rich in proteins and fats. After drying, they can be used as an additive for chicken- and fish-food. Heidelberg is in talks to sell the algae additives to major agricultural companies like Cargill. At its current size, the Algoland system in Degerhamn can only produce about a few kilograms of algae a day. But the plant has all it needs to scale up to make many metric tons of algae daily—light, water, fresh algae, and lots of space—and thus capture many metric tons of carbon dioxide in the process.

The science underlying Algoland is not novel, but what is new is how well it integrates the many parts entailed into an economically feasible carbon-capture plant. The used-up limestone quarry can provide the space; a greenhouse built on it ensures the right temperature and light is available even when the sun’s not shining; and the Baltic Sea is a source for both water and fresh algae.

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Farming for the Future on the Roofs of Hong Kong

fruit store

Green roofs are great for collecting water and cooling neighbourhoods, they are also useful for feeding their local communities. In the densely built urban environment of Hong Kong there is a network of green roofs that used for farming. These farms are used to grow crops sold in local stores and to encourage the people of Hong Kong to get their hands dirty and understand where their food comes from.

Here the team tell me about their other goal: education. By running regular workshops, the team hope that Hong Kong’s city-dwellers will become a little more aware of the resources needed to grow the food they are eating. Pointing to a bed of broccoli, for instance, Hong remembers one recent group who had never seen the whole plant. “They didn’t realise that the florets that we eat are actually quite limited,” she says. “And if you look at the quantity we see in the supermarket, you begin to see how much space we would need to grow that,” she says.

Ultimately, Tsui’s dream is that a restful break on a rooftop farm will become ingrained in everyone’s daily routine. “I use the analogy of coffee,” says Tsui – something that was once a luxury, but which became a lifestyle, through sheer convenience. If he had his way, a trip to the farm would be as essential as a morning caffeine fix. “We do have a mission, in a way – to make farming cool.”

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Waterproofing Cities for Resiliency

housing

The last month brought a lot of rain to the city of Toronto which has led to the Toronto islands being half submerged and a temporary (and lax) travel ban to be put into effect. The rest of the city has fared slightly better. The city has slowly been improving its water management over the years by implementing green roofs and providing more green space along ravines to absorb water. That’s not enough to deal with the increased rainfall from climate change. Over at the CBC they have an article looking at effective ways that Toronto is already using and what more can be done.

Of course, the techniques used in Toronto can be applied to many other cities.

The water that makes it past collection systems or soaks through green spaces ends up in Toronto’s sewer system.

In cases of a heavy downpour, that can send a mix of storm and sanitary water into Lake Ontario, due to the city’s combined sewer system.

While the city has dedicated reserves for storm water, it has no choice but to pump the mixed sewage and storm water into the lake during extreme rainfall.

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Americans Eating Beans Instead of Beef Will Help Save the World

beans

If Americans started eating beans in place of beef the country would be able to meet its greenhouse gas (GHG) reduction goals by 2020. The report, title, “Substituting beans for beef as a contribution towards U.S. climate change targets,” builds off of previous work. The new report that makes this conclusion is similar to the conclusions from other papers; however, this report directly connects an easy dietary change to being able to avert catastrophic climate change. Previously we’ve seen how easy and beneficial it is to be vegetarian, but this diet change doesn’t require a complete shift to vegetarianism. Just reduce the consumption of flesh from dead animals.

It’s simple: the easiest thing you can do today to help the people of tomorrow is to eat less meat.

“The nation could achieve more than half of its GHG reduction goals without imposing any new standards on automobiles or manufacturing,” Sabate said.

The study, which was conducted while Harwatt was an environmental nutrition research fellow at Loma Linda University, also found that beef production is an inefficient use of agricultural land. Substituting beans for beef would free up 42 percent of U.S. cropland currently under cultivation — a total of 1.65 million square kilometers or more than 400 million square acres, which is approximately 1.6 times the size of the state of California.

Harwatt applauds the fact that more than a third of American consumers are currently purchasing meat analogs: plant-based products that resemble animal foods in taste and texture. She says the trend suggests that animal-sourced meat is no longer a necessity.

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