This multifunctioning stair hides a generous bookcase underneath.

A health insurer practices what it preaches.

Want to get quickly into the tree canopy? This modular set of stairs can be quickly and easily wrapped around any tree, without doing damage to the trunk.

Architect Tamir Addadi squeezes a lot into a very small space

And when you get to the top of this, you deserve a treat.

Sweden shows how to build comfortable apartments for families, and stairs that people want to use.

Belgian architects build a tower in a barn. But my, it uses a lot of lumber.

Neri&Hu turn climbing the stairs into an experience for Bloomberg in Hong Kong.

A good, if not very accurate, idea.

Why go diagonally when you can go straight up?

160 tons of steel and 10 tons of copper never looked so good

And believe it or not, it's environmentally friendly!

There's more than one way to go up in a small space, and this is one smart alternative.

This is a big problem in old buildings: providing universal access without ruining the look of the building.

This month's Full Buck blood moon will star in the longest total lunar eclipse of the century.

An astronaut-eye's view of Hurricane Florence from the International Space Station shows why everyone is kind of freaking out.

The official naming organization has approved the names to commemorate the 50th anniversary of the Apollo 8 mission.

See the view captured by the International Space Station as the category 4 hurricane makes landfall over Florida.

Hubble just took the most detailed image yet of the eerie and mysterious Ghost Nebula, some 550 light-years from Earth.

Nicknamed 'Farout' by the team that discovered it, the celestial object is some 11,160,000,000 miles away.

For billions of years, a tiny moon has been slyly orbiting the ice giant – now the little lovely has a poetic name, as well as a surprisingly violent backstory.

To cap off a week of black hole fever, the cosmic object has now been named by a language professor in Hawaii.

Hubble's image of Messier 3 reveals what astronomers say is one of the prettiest "globular clusters" in the universe.

For the first time ever, NASA has recorded a likely marsquake – listen to the haunting tremor here.

More than just a typical aurora, researchers have now figured what powers this stunning lightshow and where it comes from.

Scientists think there is a hidden, protected ocean inside of Pluto – and the implications are wild.

Morocco is making good on it's stated goals of increasing renewable energy development, leading towards 40% of electricity from renewables over the next decade.

The Grand Inga dam will be double the size of China's Three Gorges, but big questions remain about whether ordinary Africans will actually get its electricity.

The latest figures from the EIA show renewable energy sources overtaking nuclear power in the US, through the first nine months of 2011.

Hydroelectric power is an easy choice to make if you have access to a stream or river, but this concept takes advantage of the streams running through our walls: our plumbing.

Think you need to be an engineer and spend a bundle to create a mini-hydropower generator? Think again.

Using the flow of water inside the pipes to power the water network's own monitoring devices could eliminate the need for batteries in those systems.

A new type of hydrokinetic turbine sits within irrigation canals and could power several homes from the flow of water.

World hydroelectric power generation has risen steadily by an average 3 percent annually over the past four decades.

A new study published by The Proceedings of the National Academy of Sciences serves as a great example of the interconnectedness of nature and how human activity can disrupt life-sustaining systems.

According to the International Energy Agency (IEA), by 2018 renewable should overtake natural gas to become the world's second-largest source of energy (oil is #1).

Just float the device in a river or stream and soon enough you'll have enough juice to charge a smartphone, GPS or other device.

A man named Manfred Mornhinweg found the modern world too "noisy and hectic", so he decided to build himself a house on a quiet 40 hectare piece of land in Chile.

A travel writer captures the beauty of Iceland's wilderness, but will these natural wonders exists for much longer?

A new technology developed by Korean researchers could generate electricity from the the motion of water in our toilets as well as rivers and streams, even rain drops.

For backpackers wanting something other than solar power.

A mix of wind, solar and hydro power could replace fossil fuels in every country in the world.

The project will take advantage of the sun, mountains and sea.

Lost in the woods near a stream, with some empty water bottles, wire, plastic plates, and a stepper motor, *and* you need to charge your smartphone? Try this.

Take one Estream and add moving water for clean, quiet, offgrid energy.

What to do when a church gets in the way of your water plans? Drown it.

Income for farmers, or fracked natural gas—will communities be allowed to decide?

The war on coal, it seems, may be ongoing, no matter who's in charge in Washington.

UK households can now buy 15 percent green gas and 100 percent green electricity with one easy tariff.

We used to be able to justify burning a bit of fossil gas, but we cannot anymore.