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Crystal clean energy efficiency

Inside one of the greenest buildings in the world

By Prospect Team  

The Crystal by Siemens. © Siemens

This article was produced in association with Siemens

In east London, on the edge of one of the City’s former docks, stands the Crystal. Developed by Siemens, the Crystal is a building that at first glance resembles an intersecting series of glass triangles, positioned in a location overlooking the water. It’s an impressive sight—and this architectural feat of daring is matched only by the technological innovation that is embodied in the building.

The Crystal is one of the greenest buildings in the world, constructed in order to help develop thinking about how modern cities can become more environmentally sustainable.

“The number of people living in cities and urban areas is now 50 per cent [of the global population] which is the highest it has ever been,” says Peter Daw, Cities Projects Developer at Siemens. “And that’s set to continue to grow to 70 per cent,” by 2050. The global population will also expand rapidly, he says, reaching 9bn by the same date. These two statistics combine to lend a deep sense of urgency to the task of finding new ways to structure the urban environment. The Crystal is a demonstration of what can be done, and of the techniques that can be deployed in future to help ease the strain on resources that will inevitably be felt as life in the world’s cities becomes more congested.

“We have 1,600 metres of solar [panels] on the roof, which provides 17 to 20 per cent of our electricity demands for the building. We also have solar thermal,” says Daw. “That means we can run our two ground source heat pumps which we have in the building purely from renewable energy. So our entire heating, ventilation and cooling in the building are entirely met from renewable sources.”

The building is also equipped with a highly complex environment management system, in which thousands of sensors across the building monitor a range of variables to ensure that the most efficient use is being made of energy and other systems at any given time. These systems are part of the integral structure of the building.

The result of these innovations is that the Crystal saves 43 per cent of all energy that would be used by an equivalent building. In addition, it is 90 per cent water efficient, meaning that only 10 per cent of the water used in the building is derived from the mains.

“The rest of it is captured from rain water, and cleaned to a standard where we can use it in the building,” says Daw. “We can also clean our toilet water and our kitchen water where we can use it in non-potable uses around the building, so for the irrigation of the land around the building or for toilet flushing.”

“In terms of CO2 savings, we are saving about 71 per cent compared to an equivalent building. In terms of energy costs we are saving about £500,000 a year.”

“All of the technology in the building is available now,” says Daw, who says that the ideas that created the Crystal are replicable at scale. What makes the Crystal so unusual is that all of these technologies have been combined in one structure, which was designed specifically with their use in mind.

“Cities like London are leading the way in terms of energy policy,” says Daw. “The national policy is following suit now.” London has had a policy of providing 25 per cent of its energy from local sources, which can make supply more resilient. That policy is starting to bear fruit, especially in the guise of the Green Investment Bank.

But making such radical changes to the way in which energy is provided to cities brings great challenges, especially in a place as ancient and multi-layered as London.

“It will be a challenge certainly, but it will be about picking the right combination of technologies for the sites that are being developed. There are parts of London where district heating networks will be the answer.” “But it’s certainly inappropriate technology for other parts of London.”

London is providing a strong example to the rest of the country of how cities can operate more efficiently and the Crystal especially so—Daw refers to the building as a “living lab.”

Siemens has also constructed a building in Taipei, in Taiwan, called Taipei 101, which Siemens says is the “greenest skyscraper in the world.” “Many of the building systems I was talking about in the Crystal are being operated there,” he says. The Crystal is changing London—might it go on to change the world?

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