Mars terraforming
2 views | +0 today
Follow
Your new post is loading...
Your new post is loading...
Rescooped by Jerubaal from Amazing Science
Scoop.it!

Steam from the sun: New sponge-like material converts 85% of solar energy into steam

Steam from the sun: New sponge-like material converts 85% of solar energy into steam | Mars terraforming | Scoop.it

A new material structure developed at MIT generates steam by soaking up the sun. The structure — a layer of graphite flakes and an underlying carbon foam — is a porous, insulating material structure that floats on water. When sunlight hits the structure’s surface, it creates a hotspot in the graphite, drawing water up through the material’s pores, where it evaporates as steam. The brighter the light, the more steam is generated.


The new material is able to convert 85 percent of incoming solar energy into steam — a significant improvement over recent approaches to solar-powered steam generation. What’s more, the setup loses very little heat in the process, and can produce steam at relatively low solar intensity. This would mean that, if scaled up, the setup would likely not require complex, costly systems to highly concentrate sunlight.


Hadi Ghasemi, a postdoc in MIT’s Department of Mechanical Engineering, says the spongelike structure can be made from relatively inexpensive materials — a particular advantage for a variety of compact, steam-powered applications.

 

“Steam is important for desalination, hygiene systems, and sterilization,” says Ghasemi, who led the development of the structure. “Especially in remote areas where the sun is the only source of energy, if you can generate steam with solar energy, it would be very useful.”

 

Ghasemi and mechanical engineering department head Gang Chen, along with five others at MIT, report on the details of the new steam-generating structure in the journal Nature Communications.

 

Today, solar-powered steam generation involves vast fields of mirrors or lenses that concentrate incoming sunlight, heating large volumes of liquid to high enough temperatures to produce steam. However, these complex systems can experience significant heat loss, leading to inefficient steam generation.

 

Recently, scientists have explored ways to improve the efficiency of solar-thermal harvesting by developing new solar receivers and by working with nanofluids. The latter approach involves mixing water with nanoparticles that heat up quickly when exposed to sunlight, vaporizing the surrounding water molecules as steam. But initiating this reaction requires very intense solar energy — about 1,000 times that of an average sunny day.

 

By contrast, the MIT approach generates steam at a solar intensity about 10 times that of a sunny day — the lowest optical concentration reported thus far. The implication, the researchers say, is that steam-generating applications can function with lower sunlight concentration and less-expensive tracking systems.  


Via Dr. Stefan Gruenwald
more...
No comment yet.
Rescooped by Jerubaal from Five Regions of the Future
Scoop.it!

How to make a new planet home

How to make a new planet home | Mars terraforming | Scoop.it

Terraforming Mars would involve adding water and an atmosphere, potentially turning the Red Planet into a Blue Marble. SE


Via Joel Barker
Jerubaal's insight:

planetary engineering; water, atmosphere

more...
No comment yet.
Rescooped by Jerubaal from Human(ity) Displacement Studies
Scoop.it!

This Band Of Small Robots Could Build Entire Skyscrapers Without Human Help

This Band Of Small Robots Could Build Entire Skyscrapers Without Human Help | Mars terraforming | Scoop.it
The Minibuilders could take on tall tasks, including automating another frontier of human labor: the construction industry.

Via Khannea Suntzu
Jerubaal's insight:

additive manufacturing, automation, robots

more...
No comment yet.
Rescooped by Jerubaal from Amazing Science
Scoop.it!

Should we first terraform Mars or Venus?

Should we first terraform Mars or Venus? | Mars terraforming | Scoop.it

As a future terraforming species, we take it for granted that Mars will be our first megaproject. But while transforming the Red Planet into something more hospitable for life seems the most logical — if not easiest — first step towards colonizing the solar system, it may actually make more sense to tackle our sister planet first. Because some scientists warn of a runaway greenhouse effect here on Earth, it may be prudent for us to terraform Venus first — a planet that has already undergone a carbon dioxide-induced apocalypse. And by doing so, we may learn how to prevent or reverse a similar catastrophe here on Earth.

 

Scientists are quite certain that Venus went through a runaway greenhouse effect when it was young and when it still had oceans. In those early days, and as the sun got brighter, Venus's oceans began to boil and evaporate into the atmosphere, where it eventually leaked out into space. Today, and as a consequence, Venus has an absolutely massive amount of carbon dioxide in its atmosphere, the result of poor carbon recycling (which is facilitated by the presence of liquid water).

 

As a result, Venus has essentially turned into hell. It features an average temperature of 467°C (872°F) — a temperature that's hot enough to melt lead. And its thick layer of carbon dioxide (CO2) bears down on the planet at a level 90 times greater than what we experience here on Earth. To say that Venus has a lot of CO2 in its atmosphere would be a gross understatement. Over 96% of its atmosphere consists of CO2, which it displays prominently through its thick layer of clouds that float 50-70 km above the surface.

 

If we wish to remove 98% of the mass of the Venusian atmosphere in a reasonable time, say, 100 years, we must haul up a mass 10 quintillion tons, or 300,000 tons per second. Compare that to the flow along the Amazon river...10,000 tons per second. The largest machines built which handle flowing water...handle 400 tons per second. Or look at it from an energy requirement: hauling the mass of gas 100 km high, and then accelerating it by 20 km per second requires about 1025 ergs over a 100-year period. That's all the sunlight falling over the same period on an area of 10,000 square km assuming 100% efficiency...Throw in a factor of 10 for engineering reality, and the air scoopers must have an area of...three times the total area of Venus.


Via Dr. Stefan Gruenwald
Jerubaal's insight:

planetary engineering: Venus has an absolutely massive amount of carbon dioxide (CO2) in its atmosphere

more...
No comment yet.
Rescooped by Jerubaal from Kool Look
Scoop.it!

How we will terraform Mars

How we will terraform Mars | Mars terraforming | Scoop.it
NASA's latest Mars rover, Curiosity, is currently its way to Mars, on a mission to explore whether life could exist there. If we're going to colonize Mars —

  Mars' geological history is divided into three ages, which are from oldest to youngest the Noachian, the Hesperian and the Amazonian. The Noachian epoch, ranging from about 4.1 to about 3.7 billion years ago, is characterized by heavy asteroid bombardment and abundant surface water. This is the so-called "warm, wet" period. The Hesperian, ranging from 3.7 to somewhere between 1.7 and 3.0 billion years ago, is characterized by heavy volcanic activity and massive water flow. The Hesperian was an intermediate age between the warm wet Noachian and the the cold, dry Amazonian, which is the Mars we know today as being not the kind of place to raise a kid.

  It is this unique history that makes Mars such an attractive candidate for terraforming. Unlike the other bodies in the solar system, Mars has a history (ancient though it may be) of being far more Earthlike than anywhere else in the solar system short of Earth itself. The proposals for terraforming the other bodies in the solar system are all highly theoretical, involving massive energy flux and near magical technology like changing planetary orbits, speeding up planetary rotation, sequestering hundreds of bars of atmosphere (1 bar = atmospheric pressure at sea level on Earth) or constructing planet-wrapping Dyson spheres to prevent atmospheric escape.

  By contrast, Mars, with its 24 hr 37 minute day, relatively abundant water ice and history of warmer wetter conditions seems more within the grasp of near future human civilization to terraform. Add to this the fact that not-too-crazily-optimistic estimates of Mars' current conditions suggest that increasing the atmospheric pressure and temperature to more life friendly conditions may be more a matter of a nudge than a shove and it's easy to see why this world holds such fascination for would-be planetary engineers.


Via David Anders
Jerubaal's insight:

Mars terraforming, planetary engineering

more...
No comment yet.