The Greener Truth » Energy

My Favorite Comic

Aaron Midgett — Mon, 09 May 2011 20:21:12 +0000

If you are interested in what renewable energy scientists do when we are not solving the energy crisis, here is one of my favorite comics from some friends of mine called Life in the Cube. They have promised me that there will be more Green comics in the future, but for now just have a laugh (if you agree with me that it is funny).

So Much for Renewable Energy

Solving the Energy Crisis

Aaron Midgett — Thu, 24 Mar 2011 14:58:17 +0000

I apologize for not posting recently. As many of you may not know, I am a graduate student and I am defending my thesis in two weeks. This has meant that work has taken precedence over the more interesting task of blogging. Until I have more time, here is the beginning of the introduction to my dissertation that I thought would be interesting to the majority of you. Hope you get something out of it, and in a few weeks, I will try to get back to a regular blogging schedule.

The Energy Crisis

Coal Power Plant

The motivation behind the search for cost effective, carbon neutral, renewable energy sources is readily apparent in all areas of our daily life. Since the industrial revolution, the human need for high quality, inexpensive energy has driven both exploration and technology. For most of that time, that need was filled by fossil fuels, which today comprise 85% of the U.S. energy supply. Since their rise to power in the industrial revolution, fossil fuels have always been readily available and inexpensive. The problem with fossil fuels that the cost of mining and distributing coal and oil does not take into account is their cost to the environment and their finite availability. Because of these two missing factors, fossil fuels are sold for considerably less than their true costs, on a larger scale, meaning that other energy sources are not able to compete. This has meant that for the last two hundred years, fossil fuels have had a monopoly on the energy market, while slowly changing the climate of our planet. We have now come to expect an unlimited supply of relatively inexpensive energy, and therefore, any replacement must be cost effective, easily transportable and widely available.

Power of the Sun

Based on these criteria, there are a limited number of sources that are capable of providing the energy needed, and none that can do so for the same price that oil, coal and gas are sold for today. The most obvious untapped energy source is harnessing the power from the sun. More energy strikes the earth, in the form of sunlight, in a single hour (4.3 x 10²⁰ J) than humans consumed on the entire planet in 2001 (4.3 x 10²⁰ J). The current technology for collecting this energy is insufficient. While fossil-fuel-derived energy can be produced for as little as $0.02-0.05 (kW-hr)^-1, the average cost of solar cells, based on a twenty year lifetime, are in the range of $0.21-0.46 (kW-hr)^-1for a commercial utility scale power plant. Due to the large discrepancy between the costs of these two energy sources, incremental improvements to the cost of solar cells are not enough, and instead, new revolutionary ideas must be implemented that are not only more cost effective, but also more efficient. This is the area of solar research categorized as third generation.

Solar Cells: Generating Electricity from Light

Thanks to Tree Hugger and the Pope

Solar cells are designed to absorb photons from sunlight and convert that energy into electricity by taking advantage of the photovoltaic effect and separating an electron and hole across the bandgap of the semiconductor. If a photon does not have enough energy to excite an electron across the gap, it will either be transmitted or scattered. On the other hand, if the photon has more energy than the bandgap of the semiconductor, the excess kinetic energy is lost to heat as the high-energy electron and hole cool to the bandedge. Once the electron is separated from the hole, a built in asymmetry in the device (usually created with a junction of electrically different materials) causes the electrons to flow through an external circuit where they can be used to do electrical work.

The delicate balance of collecting the most photons possible while keeping the highest voltage based on the solar spectrum creates an upper limit to the theoretical efficiency of a traditional, single bandgap, terrestrial solar cell. This detailed balance calculation, originally defined in 1961, leads to the Shockley-Queisser limit of 30-33% for solar cells with bandgaps in the range of 1-1.6 eV. While some of the energy loss is due to the transmission of low energy photons, the majority of the lost energy (almost 50%) is due to heat created as the high energy charge carriers cool to the bandgap. By accessing this lost energy, the theoretical efficiency of a solar cell increases, and the goal of third generation solar is realized.

Peddle Power at the Copenhagen Crowne Plaza

Aaron Midgett — Tue, 20 Jul 2010 23:11:49 +0000

I have often fondly talked about my experience with biking in the Danish capital Copenhagen, but a the Crowne Plaza has come up with a great idea to take this to a new level. They have installed two bikes in the hotel lobby that are used to generate electricity. This by itself is a brilliant idea, not so much different from the idea of a gym powered by the patrons (one of our Greener Truth bloggers has always wanted to start a gym like this called the Powerhouse), but they have taken this idea a step farther and passed the savings along to the people doing the work. If you are staying at the hotel, a short workout on the bikes will earn you a free meal or drinks at the bar. This is the first such program that I know about and the Crowne Plaza is using this as a test program before expanding to other hotels. On top of this idea, the hotel was designed with energy saving in mind and uses 90% less energy than traditional buildings. Here are just a few of the energy saving ideas that have been implemented.

-solar pannels on the roof and exterior

-a geothermal well for heating and cooling

-the use of a biogas facility for organic waste

-organic food

-water saving faucets

-low energy lighting and electronics

I think that this is a great idea and would love to see these sorts of ideas catch on. To date, most business think of green practices as costly and unnecessary, but ideas like this will show that it is possible to run a greener business and save money as long as people are willing to think out of the box.

Sail Across the US on a Pterosail

Aaron Midgett — Fri, 09 Jul 2010 03:47:42 +0000

I am always excited about new eco adventures, and here is one that I think would be a ton of fun. The Pterosail is a recumbant trike that is equiped with a special stable sail. For me, this is the perfect combination, because I love riding a bike and sailing. When I was 12, my grandmother gave me lessons in a little sunfish, and since then, I have always loved being on the water, but now that I live in colorado it is chalenging to get to an ocean. The Pterosail solves this problem, and they will be proving it over the next few weeks. On June 28th they started a journey from San Diego, CA to St. Augistine, FL. So far they are averaging 50-60 miles a day thanks to the wind and the sun. Along with the sail and peddle power, there is also a solar pannel that rides above the driver and powers electronics and a small electric backup motor. I am sure that they are getting some wierd looks, but at this rate it won’t be long before they make it to the Atlantic. Right now, these wind powered trikes are crazy expensive ($5500), but I hope that with time that will come down some. From my experience traveling by bike, I am sure that this is a great way to see the country and I hope one day I will get a chance to try it out.

More information on Sail Bikes

-Pterosail

-EcoFriend

-SolarFeeds

Flaming Tap Water is Fracking Crazy!

Aaron Midgett — Thu, 01 Jul 2010 20:48:33 +0000

Considering all of the horrors of the gulf oil spill, I don’t think that there is an American left that doesn’t wish for a better alternative than oil. Then again, with some of the responses floating around lately, maybe I am wrong. Natural gas, which many tout as a greener alternative than oil, has become more popular and accounts for 17% of Us electricity and over 50% of heating. It is true, that natural gas releases less carbon dioxide and other pollutants per unit of energy released, but the consequences shown in this video from the new documentary Gasland blew me out of the water.
YES, if you were wondering, that is the tap water catching fire! And by the way, this is not because of some horrible spill, but just a normal (and expected) consequence of extracting natural gas from the ground. As explained in the video, this is caused when natural gas companies use a process called fracking (hydraulic fracturing) that releases the gas buried deep in the earth so it can be extracted. The side effect of this this process is that natural gas leaks into the water supply, leading to contamination and eventually tap water that catches fire. Here is a great article from the makers of the movie Gasland that explain fracking and natural gas production in more detail.

More Information about Natural Gas Production

-Gasland the Movie

-What is Fracking

-Wikipedia: Hydraulic Fracturing

-Wikipedia: Natural Gas

DOE asks for Suggestions on how to Stop Oil Spill

Aaron Midgett — Wed, 23 Jun 2010 17:17:30 +0000

It is hard to believe that the oil spill is still gushing as much as ever and that we still have no idea how to fix it . To top it off, our politicians are too busy arguing over money and apologizing to BP to do anything productive about the situation. We haven’t even effectively paused off-shore drilling in the gulf of mexico due to the recent legal setback. John Stewart says this better than I could.


Day 62 – The Strife Aquatic
www.thedailyshow.com

Because of my work at a national lab, I get e-mails from the Department of Energy, but this one from last week really surprised me.

Subject: DOE Email Address for Deepwater Horizon Solutions

Employees are encouraged to submit ideas and suggestions in topic areas including, but not limited to: sub-surface containment, surface containment, shoreline cleanup and remediation, safety improvements, and flow stoppage. Effective immediately ideas should be sent to oilspillsolutions@hq.doe.gov

As part of the Department of Energy’s response to the Deepwater Horizon oil spill in the Gulf, the Office of Fossil Energy has established a new email address to collect the best ideas from within the Department’s research community (i.e. DOE labs, universities, contractors and others that interact with DOE) on how to stop or contain the oil’s release and mitigate impact on the environment. Please send ideas and suggestions directly to oilspillsolutions@hq.doe.gov. Submissions will undergo an internal vetting process and the most immediately applicable suggestions will be elevated to senior DOE leadership for accelerated consideration.

However, ALL suggestions will be placed in the Government’s public Deepwater Horizon database for evaluation by an interagency team. This will ensure that innovative ideas, which are directly applicable to the Deepwater Horizon oil spill, receive the highest attention.

Working with the Department of Energy, I know how many smart people there are working here, but this seems a little desperate. The only thing that most people know about the spill is what we hear on TV and it seems a little unreasonable to expect us to be able to put fourth an effective solution without doing a better job of outlining the details of the problem. Here is a start at explaining the technical details if you happen to be up for taking on the challenge. This is a disaster on an unprecedented scale (I am not going to say how big because we can’t even tell you that accurately) and we need to learn something from it. Going forward, I think that it is important to learn from this mistake and in the short term use a lot more caution in oil exploration, while focusing on the long term goal of weaning ourselves off of oil and onto renewables. The cost of fossil fuels is much higher than the price that we pay at the pump and if this is the disaster that makes the world realize that, then maybe we can turn a horrible situation into a turning point for the energy economy.

More information about Deepwater Horizon Oil Spill

-DOE

-Wikipedia

Most Honest Ad for Oil Ever!

Aaron Midgett — Wed, 16 Jun 2010 16:10:07 +0000

With all of the greenwashed adds for oil companies like BP, it is nice for a change to look at and add that really speaks the truth. This ad by Humble Oil (now part of Exxon) from 1962 is possibly the most honest straight forward add I have ever seen.

Maybe BP needs to take lesson from Humble and start putting out a little more honest ads too instead of hogwash like this.

Cost of Transportation

Aaron Midgett — Thu, 20 May 2010 23:06:21 +0000

When we talk about forms of transportation, we are often interested in fuel economy because that is what we are used to, but what really matters is the amount of energy it takes to move a certain amount of weight a certain distance. We have tried to represent this in the WAVE scale in our automotive section, but here is an old graphic that I found that explain this idea a little better. You can tell how old it is by the fact that it was scanned from a journal article in order to digitize it. You can see the obvious diagonal where most of the methods fall. Lighter and smaller animals use more energy to move one gram a kilometer as would be expected, but it is the outliers in this plot that are the most interesting. If we look at a helicopter for example, its cost of transport is similar to that of a hummingbird and obviously wastes a large amount of energy. Salmon and humans on a bicycle on the other hand, are far more efficient than other forms of transportation . The salmon is a particularly interesting case, because it actually uses the flow of current downstream to help it swim upstream, similar to the way that a sailboat can sail into the wind.

More information on Fuel Economy and the WAVE scale

-The Wave Scale

-Weight Friend or Foe

-FuelEconomy.gov

-EPA

-Wikipedia

Granola for your Computer

Aaron Midgett — Thu, 13 May 2010 20:34:35 +0000

By Guest Author: Josh Holt
PhD Scientist at the National Renewable Energy Labratory

About a year ago, I began thinking about how much electricity my computer used. I’m not talking about using my computer, but about not using it. Really, how much of your computer do you really use? I’m watching the resource meter right now as I’m typing and the CPU history rarely spikes above 25%. That’s when I’m “using” it. Most of the time it spends on, I spend in the other room.

Your computer power supply is rated in Watts, just like light bulbs, and is built into the design of the whole computer to handle the maximum power load that all the hardware could possibly require. For average systems, that maximum rating is somewhere between 250-400 Watts. However, higher-end hardware such as hefty video cards for gaming or large monitors, multi-core processors, cooling fans, multimedia encoding/decoding, optical disc drives (say, burning DVDs), multiple or high-speed hard drives, or other power-hungry components can bump that peak demand above 1000 Watts. Most of the day you probably float at less than half your peak power. Even so, your computer can easily draw 100 Watts idling. Did you ever think of your computer as an extra light in your house, one that you leave on when you leave the room, or, like some people I know, while you’re sleeping? Sure, I try to turn off my computer when I don’t need it (I usually get more done then anyway), but sometimes it’s just not practical. When that extra proverbial light bulb needs to be on, wouldn’t it be nice to dim the lights when only need mood lighting or you leave the room, while still enjoy the brightness when you need it? Enter Granola.

Granola is software that does just that. It emerged out of beta on Earth Day 2010 and, best of all, it’s free and runs on Windows and Linux, and may be planned for Mac OSX down the road. Formerly MicroMiser, Granola was renamed to “more accurately capture our goal of making a serious impact on the planet through the reduction of wasted energy,” says MiserWare, the company behind Granola. According to the email they sent me announceing the newest version: “There are over a billion personal computers in the world. Together, they consume hundreds of billions of kilowatt hours annually. If each of these computers ran Granola and reduced their power consumption by even 10%, it would be like taking 7 million cars off the road. Or planting 900 million trees. Or turning off 65 coal power plants.” So far, they claim that the Granola community has saved as much CO2 as tens of thousands of trees. That’s assuming that every download equates to “average saving” of 56.9kWh and runs on a computer 24/7. Even though reported numbers seem to be best-case scenarios based on assumptions and averages, more awareness of green-aware computers goes a long way, especially with the climbing ubiquity of personal computing. And to be honest, if there’s any chance of trimming my electricity bill, I’m interested.

I have Granola running on three linux computers at home: a newer quad-core CPU computer, an older single-core CPU computer, and a small server with an low-power Intel Atom processor. Granola saves a bit over 45% CPU energy on all three, and claims to save about $25/year each, after setting our local energy rate to $0.10/kWh. Scale that by how often they’re on, and the savings comes to about $40/year. My wife claims to notice her computer runs a bit slower, but I don’t notice much change on mine. Next step is to find a Kill-A-Watt meter to check the power savings.

But Granola can only throttle the CPU power. Other managements are built into your operating system to quell power draw, such as timing monitor power-off, spinning down the hard drive, or hibernating, which are especially appreciated on laptops. The sure-fire hacks to save computing energy still remain: use laptops instead of desktops, turn them off when not in use, and don’t buy higher performing systems than life demands. But if those don’t work for you, Granola can bring some peace of mind and a little green to your CPU.

More information about Green computing and Sustainable Electronics

-Sustainable Electronics

-Grano.la

-University of Colorado

-Wikipedia: Green Computing

-Recycling Electronics

A picture says a Thousand Words: Oil Edition

Aaron Midgett — Tue, 11 May 2010 18:08:25 +0000

Some times it is difficult to put disasters, such as the BP oil spill into perspective, but I thought that these few graphics, did a great job of that. The first, from Information is Beautiful, shows both the size and the impact that this spill is having. The fact that it is steadily approaching the largest spill in history without any signs of stopping is a little disturbing .

thanks to Information is Beautiful

Fake Science and Despair, had their own interpretation that is quite fitting (if a bit cynical).