Tag Archives: solar power

What do HMNS, Superman, Stargate and steampunk have in common? Find out on May 25 at Comicpalooza

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If you’ve been to the Wiess Energy Hall recently, you’ll remember the energy music video that starts off with “Energy is all around us.” Energy is all around us. It’s in the news every day. It’s also a prominent feature in sci-fi, comics and steampunk.

For more than 45 years, we’ve had a certain Scottish engineer talk about the need to power his engines. The mighty Starship Enterprise was propelled across the galaxy by warping space around it using a matter-antimatter reaction. (Antimatter has the same mass as matter but is oppositely charged — positron to electron and antiproton to proton).

We currently use antimatter in Positron Emission Tomography (PET) scans. While an antimatter reaction can give us 9×10^16 J/kg (note: dynamite is about 4.6×10^6 J/kg and a nuclear reactor is 5.6 x 10^9 J/kg ), it’s hard to bring into existence and even harder to keep around. In 2011, CERN was able to get about 300 anti-hydrogen atoms to hang around for about 17 minutes. While far less time than Dan Brown had it around for, it’s still a great achievement — especially since you can’t hold antimatter in a container made only of matter. You have to use a combination of electric and magnetic fields to make sure it does not go “boom.” NASA is looking into this as a propulsion system for interstellar transportation (possibly because rocket scientists grew up watching Star Trek), but it’s still far in the future.

Some of us have a fond memory of Rodney McKay yelling about the zero point module (ZPM) not having enough power to protect the city for long. (If you just got that reference, smile, because you are a nerd.) To get even more nerdy, there is such a thing as zero point energy. It is the least amount of energy a quantum system may have, or the energy produced when all is at rest. This is because of the wave-like properties of matter.  It’s also the reason that liquid helium will not freeze.

Is there a way to harvest all this background energy? Unfortunately, not yet. Because of the zero point in the minimum amount of energy the system can have, if you were able to take it away, the amount of energy would drop below its limits. In Stargate, they get around this by containing microuniverses in a handheld containment vessel and harvest the zero point energy from them (what happens when the ZPM runs out of energy? Is that universe dead?).

Sooper dpoper man

It’s a bird, it’s a plane, no, it’s a solar-powered man!

Superman, one of the most iconic and archetypal characters, receives his power from our yellow sun (and in Miller’s Batman Returns, he can take it from sunflowers as well). Because he uses green fuel, he can lift cars, leap buildings, be directed by Zack Snyder, and get Amy Adams. If only this were true for everyone who goes green. *Sigh.*

It is nice to have a superhero, even from the ’40s, that is looking toward the eventual infrastructure shift to renewables. Just as Superman’s war against falsehood and injustice has yet to be completed, we still have to wait for the switch. Unlike fighting against Doomsday and General Zod, we can do things to help speed the switch over to renewables.The easiest thing is to use less energy. If you’re more adventurous, you could look into the tax rebate programs for buying solar panels.

Steampunk is perhaps the most focused on energy. It’s in their very name. “Steampunk” is a sub genre that focuses on having mechanisms only powered by steam. While most steampunks look back either to Victorian times (call ‘em Vickies) or to the post-apocalypse, we are still in a steam age.

Almost all of our electricity is steam-powered. Coal, natural gas plants, and nuclear power plants all create electricity by turning water into steam and having that steam turn a piece of metal around a magnet (albeit on a large scale).

It can be exciting to see how you would come up with a steam driven alternative to a lot of modern technology. How would you construct a large airliner if it has no electronics and could only rely on hydraulics? Personally, I always hope for a dirigible-like air ship in which to battle sky pirates, but that may just be me.

An institution that you may readily associate with both a comic convention and energy is the Houston Museum of Natural Science. Museums may have a reputation of being dusty old cabinets of curiosities, but not us. So drop by our booth at Comicpalooza on May 25 and see what we’re up to.

Add it up: Doing the math on electric cars

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Editor’s note: The opinions expressed by our contributing staff writers are their own and do not necessarily represent the opinions of the Houston Museum of Natural Science.

Electric cars are a popular idea. You see them in movies, hear about them in songs, and especially get to know them via inventive commercials. They claim that they produce no pollution, unlike their dinosaur automobiles with the internal combustion engines. But are they as green as they claim to be? (Note: For this blog I’ll be talking about pure electric cars, not hybrids.)

Doing the math on electric cars

A normal gasoline-using car produces pollutants as a result of converting fuel into movement. An electric car uses stored electricity to propel the vehicle. But how much pollution was created while creating the electricity? To compare the two, we’ll have to find some way to make gasoline and electricity equivalent. Fortunately, we can convert both to one unit: joules. While you might want to wear a jewel, a joule will help you get work done. A joule (abbreviated by “J” ) is a unit of energy. It’s the equivalent of applying 1 ampere through a resistance of 1 ohm for 1 second, or the force of 1 Newton over 1 meter.

A gallon of gasoline contains about 1,300,000,000 joules. One kilowatt of electricity contains 36,000,000 joules. So 1 gallon of gas produces about 36 kilowatt hours.

Burning a gallon of gasoline to move your car produces about 20 pounds of carbon dioxide. One kilowatt hour can produce different amounts of carbon dioxide, depending on what energy source was used to make it. In the United States, much of our electricity (about 42 percent) comes from coal-fired power plants. One kilogram of coal can produce 2 kilowatt hours and 2.93 kilograms of carbon dioxide. That’s about 3.3 pounds of carbon dioxide per kilowatt hour, which means that 1 gallon of gas’ equivalent in electricity produces 118 pounds of carbon dioxide if all the electricity is made from coal-fired power plants. From this information, it seems that the internal combustion engine outperforms the electric, but not all electricity comes from coal.

While the majority of our electrical generation comes from coal-fired power plants, there are other energy sources. Thirteen percent of our electricity comes from renewables such as wind and solar power, which produce no carbon dioxide. Nuclear power gives us 19 percent of our electricity and produces no carbon dioxide, either. Using this division of power sources, the amount of carbon dioxide produced making electricity for an electric car has been reduced from 118 pounds to just 8. But what about natural gas?

Natural Gas is measured by the MMBTu (one million British thermal units), which is about 1,000 cubic feet (1 mcf). One mcf of natural gas produces 122 pounds of carbon dioxide and can produce about 29 kilowatt hours. Are you still with me? This means that natural gas produces about 4 pounds of carbon dioxide per kilowatt hour. So when we add that back into the mix, our electric car is producing about 9 pounds of carbon dioxide per kilowatt hour. A gallon of gas is about 36 kilowatt hours and produces 20 lbs of carbon dioxide, or about half a pound of carbon dioxide per kilowatt hour.

Does that mean that electric cars produce more carbon dioxide than ones that run on gas? Maybe, maybe not. All those numbers are based on the national average of the energy mix. If renewables provide more electricity in your area, the amount of carbon will decrease. If you get your electricity from an all-renewable company, then you’re producing no carbon. Also, this blog has only addressed the amount of carbon dioxide produced directly by energy sources. It has not included all the other pollutants produced. It has not included the entire life cycle of the energy source. For example, a nuclear reactor produces no carbon dioxide, but mining uranium is a very energy intense project. Wind turbines produce no carbon dioxide while creating electricity, but carbon dioxide is produced when they are built.

The amount of carbon dioxide produced by electric cars can be brought down easily, where the amount produced by internal combustion engines can not. yo could switch the source of electricity. You could take stored electricity and use it for you car. Because our grid is a stupid grid and not a smart grid electricity is put on the grid as needed. If there is a moment with high wind generation and a high need for electricity, then the amount of carbon produced decreases. If the wind stops blowing and the need is still there, then the more traditional sources kick in and the amount of carbon produced goes right back up.

So while an electric car, on average, may currently produce more carbon dioxide than a gas-powered car, depending or your location and your electric provider, your electric car may be producing no carbon dioxide. Also, while there is little hope to improve the internal combustion engine to eliminate the production of carbon dioxide, researchers hope to eventually eliminate the carbon produced by an electric car. So “Let’s take a ride in an electric car/To the west side in an electric car/How can you deny an electric car/Won’t you take a ride with me/Come on and take a ride with me!”

The Bear Necessities

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If you would be wealthy, think of saving as well as getting.
Benjamin Franklin

When I was younger, my parents would read to me before I went to bed.  I would hear tales of adventure and science from Tom Swift, Jr. and tales of mystery from the Hardy Boys, and the fantastical from The Hobbit.  They would also read the Berenstain Bears to me.  If you’re unfamiliar with this series, it’s about a family of bears that face situations that are likely to be faced by children and parents.  The Bear family consists of Papa Bear, Mama Bear, Brother Bear, Sister Bear, and, since 2000, Honey Bear.  There have been more than 260 books in the series.  In the books, Brother and Sister bear learn many valuable lessons, like what happens when you watch too much TV (The Berenstain Bears and Too Much TV), eat to much junk food (The Berenstain Bears and Too Much Junkfood) (hurmmm American public), or about earning and saving money (Wall Street)… I mean Trouble with Money.

The one that made a lasting impression on me was The Messy Room (da, da, daa).  In that book, Brother and Sister have a messy room and can never find anything (they even forget that they have some things) and their parents come up with an idea for storage.  Clearly labeled boxes stacked in the closet.  And then their room is clean (I’m still working on it myself, is it messy if I know what’s in all the piles?).

The current (that pun again) electrical infrastructure is like that messy room.

Wind Energy
Creative Commons License photo credit: l.bailey_beverley

The current electrical grid operates on a “use or lose” bias.  Meaning that only the amount of electricity needed at any given moment is on the grid.  If an energy source, like a wind turbine in West, Texas produces more electricity than the grid can use, it is bled off as waste.  If the amount of electricity needed increases, then short start up generators go online and once the demand is over they shut back down.  That strikes me as a very dumb grid.

One of the large hurtles in making a smarter grid is electrical storage.  We are all used to some forms of electrical storage.  We have alkaline batteries lying about our houses (except AA, I can never find any, but I’m sure they’re just over there…).  These work by producing electricity through the reaction of zinc and magnesium dioxide. They make up 80% of the batteries in the United States.  People have also gotten familiar with the lithium ion batteries which are found in most mp3 players and some phones. Lithium ion batteries are rechargeable, but through many recharges slowly loose the ability to hold a charge.  Lithium sodium batteries are in the works that can hold more energy and be a little less expensive.  One way to get batteries for your home is to get the old batteries from your hybrid car.

Chemical batteries are not the only way to store electricity.

Engine & Flywheel
Creative Commons License photo credit: Howard Dickins

Another way is to store the energy as compressed air.  The excess electricity is used to compress air, and when the electricity is needed the air is let out and turns a turbine.  Compressed air has been used for energy since the 1870s in Paris, London, and other cities. Another way to store electricity is the use of fly wheels.  The excess electricity is used to power up a rotor in a spinning motion.  When electricity is needed, the movement of the rotor is converted back into electricity. The new Gerald Ford class super aircraft carriers will make use of flywheels to help launch planes.  One of the main technical concerns is friction.  Too much friction and too much energy is lost. One of the most efficient ways to store up electrical power on the large scale is pumped water. The excess electricity is used to pump water up in a holding chamber or reservoir.  Then when electricity is needed, the water flows back down.

Electrical storage is also important for renewables.  Solar power can be unreliable.  Because of the rotation of the earth, solar power can be reliably unreliable.  Solar power can only be gathered when the sun is out.  Most of the time the sun is out, I’m at work.  There are usually only a few days a week when I get to see the sun.  Therefore, most of my electrical needs happen when solar power is not an option.  If I had a way to store it while I was at work, then I would use it when I got home. The same is true for wind.  Despite the United States being full of hot air, wind does not always blow.  Wind generated electricity can sometimes be too much for the electrical grid.  If the excess were stored, it could be used when there’s no wind a blowin’.

Small scale electrical storage would also help small scale renewables.

If I have a small scale solar panel, a small wind turbine, and a small water pump all tied up with some sort of electrical storage, I can take the electricity I gather in and only use it when I need it.  That way if the sun shines, the wind blows, or the rain falls while I’m away, I can come back and have Mother Nature power my computer.

Ride on a Shooting Star: Space Fuel

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After the decimation suffered during World War II, mankind took a look at all the new technologies he had created to fight the war and turned his gaze towards the stars. From the late 1940’s this onward and upward reach has helped to fuel the engines of our ingenuity, but what has fueled those stellar ambassadors that now dot our solar system and beyond.

654 - Galaxies - Seamless Texture
Creative Commons License photo credit: Patrick Hoesly

To move from the surface of the earth to this new ocean a rocket must be moving about 7 miles per second. That takes a lot of energy. Many different propellants have been used. The very first rocket fuels were a mix of kerosene and liquid oxygen. Alcohol, hydrogen peroxide, and liquid hydrogen have also been used, in addition to solid fuels. They can provide thrust without the need for all the refrigeration and containment equipment that some of the liquid fuels, such as liquid hydrogen and oxygen, require.

Once the probe is beyond the reach of the atmosphere there is no way to change what’s on board.

The probe cannot drop by the local Radio Shack and pick up a fresh pair of AA batteries. While the probe is being built on Earth, the engineers must make sure that they provide a source of power that will give the probe the right amount of power.

Too little power and the scientific instrumentation won’t work; too much power could over heat the probe. On board chemical batteries can be used, but they take space that could be used for scientific instruments. Solar panels can be used, but only up to a certain distance from the sun. Beyond the orbit of Jupiter, probes need an internal power supply that will last for years.

They use the heat from radioactive decay of fissionable isotope.

Sputnik 1 in Orbit Sep 10-4-57
Creative Commons License photo credit: FlyingSinger

Early probes like Sputnik and Explorer 1 used chemical batteries to power their systems. In March of 1958 Vanguard 1, the 4th artificial satellite and the 1st powered by solar power, was launched. Probes with solar panels have more space on board for scientific instruments than probes that use only chemical batteries. Probes sent into the inner solar system (sun to Mars) are almost all powered using solar arrays.

Mariner 2, the first USA probe to Venus, suffered the loss of one of its solar arrays, but because it was closer to the sun, it was able to operate using only one solar array. No American manned space craft have made use of solar arrays yet (the new Multi-Purpose Crew Vehicle may), the Russian Soyuz spacecraft have used them since 1967.

The International Space Station (ISS) is the largest man-made structure outside our atmosphere.

Larger than a football field (but smaller than a football pitch), this outpost orbits the earth every hour and a half. It is also powered completely by solar power. Past the atmosphere, solar power becomes more practical and more consistent (there is no night in space). Because of the orbital path of the ISS, it is eclipsed by the earth for 30 minutes out of every hour and a half. The station makes use of rechargeable batteries to make sure it is never without power.

From a Distance
Creative Commons License photo credit: Undertow851

As the probes go farther and farther away from the sun, the light that can reach them is less and less.

Until August of 2011, no probe to Jupiter had ever been powered just by solar panels. Juno, the latest probe to Jupiter, has the largest solar arrays given to a deep space probe and the first probe to Jupiter to use solar arrays.

Jupiter receives only 4% of the sunlight we enjoy on Earth. Advances in solar technology have now made it practical to use solar panels out 5 Astronomical Units (AUs) from the sun. All other deep space probes have used a radioisotope thermoelectric generator (RTG).

A RTG works by converting the heat from the decay of a radioactive fuel into electricity. American probes have been using Plutonium 238 (an isotope of Plutonium) since the late 1960’s. It has a half life of about 88 years. RTGs have powered all our interplanetary probes (the Voyagers and Pioneers and soon to be New Horizons). However, NASA has begun to run out of fuel for the RTGs and the creation of more is full of political and safety considerations.

There he goes, after an all day long work.
Creative Commons License photo credit: giumaiolini

The technology that we’ve made to go out to the ‘verse with will also help us here on the cool, green hills of earth. RGTs have been used, mainly by Russia, to provide power for off the grid light houses. Advances in solar panels for space are used down here on Terre Firma. With the reliably of solar power in space, there are even attempts to construct orbital solar collectors to beam down electricity. There will be from heaven to Earth more than is dreamt of.