Stories tagged renewable energy

Oct
18
2011

With the exception of the Family Christmas Flu of 2002, I haven’t stopped to appreciate the toilet much in my life. However, Dr. Richard Alley’s presentation at the Science Museum of Minnesota on October 6th really made me think about toilets – and the waste we flush – like I never had before.
Authentic chamber pot: Nothing pretty about it
Authentic chamber pot: Nothing pretty about itCourtesy Evelyn Simak

Today, we can’t imagine living without toilets or indoor plumbing, especially in populated areas for extended periods of time. Gone are the days of the chamber pot, the daily hurling of human waste from your window into the street below, and the pervasive stench that resulted.

It’s really incredible to think about how society went from chamber pots to toilets. I mean, there is a HUGE amount of technology development, public policy, and civil engineering involved in the invention, installation, and maintenance of plumbing infrastructure. (You never thought about it either, did you?) You have to invent the plumbing fixtures, convince the government and the public that it’s a necessity, perfect the manufacturing process, install miles of underground pipes, build collection and treatment plants, and continually upkeep the entire system.

The daunting obstacles must have made indoor plumbing seem virtually impossible back in the day, but we did it anyway, which raises two really great questions: How and why?

How we made the switch from chamber pots to toilets is less important than why we made the switch because we probably wouldn’t have bothered to figured out how if we didn’t have a dang good reason why to put in all the effort. Like grandma says, “Where there’s a will, there’s a way.”
Authentic toilet: Something pretty about it.
Authentic toilet: Something pretty about it.Courtesy 13th Street Studio

We put in the effort to move towards toilets because we realized we couldn’t keep living with chamber pots. Chamber pots were unsightly, smelly, and really bad for public health. After we became convinced of the necessity of toilets, we figured out how to do it and we even put up with the disruption their adoption created. A few generations later and we can’t imagine living any other way.

Dr. Alley says we’re now on the cusp of our own epic Chamber-Pot-to-Toilet story.

Today, we can’t imagine living without fossil fuels as an energy source, but our grandchildren might not be able to imagine what it’s like living without renewable energy. Chamber pots and excrement are like fossil fuels and pollution: unsightly, smelly, and bad for public health. Hopefully, like with toilets, we’ll eventually realize we can’t keep living in our own filth and we’ll find a way to widely adopt renewable energy to replace fossil fuels.

According to Dr. Alley’s presentation, we already have the technology to capture enough renewable energy to cover the world’s current energy usage (15.7 terawatts) with some to spare, and the amount of renewable energy available for capture in the future is simply staggering. That means we should also be able to serve populations that do not currently have energy access and provide energy for our future's growing global population – all sustainably! Sure the technology development, public policy, and civil engineering involved in switching to a new energy system is daunting, but it can't be much longer until we realize it's a necessity worth the effort.

You can watch segments of Earth: The Operator’s Manual online (including Dr. Alley's 30 second introduction of himself, check out 1:23-1:53) and even read the annotated script. Segment 9 of Chapter 3 (beginning at page 98 of the annotated script), Towards a Sustainable Future, covers the details of which renewable energy sources we could use to create a global sustainable energy portfolio.

Why hasn't someone thought of this earlier? The Cincinnati Zoo has installed solar cells over about 800 spaces of its 1,000-car parking lot. The cells will generate enough electricity for about 20 percent of the zoo's power needs. And zoo visitors will return to cooler cars at the end of their visit.

Sep
02
2010

Electricity in the air: Some of our energy needs may someday come from the atmosphere.
Electricity in the air: Some of our energy needs may someday come from the atmosphere.Courtesy wvs (Sam Javanrouh)
In a paper delivered at the 240th National Meeting of the American Chemical Society in Boston, a researcher envisioned a time in the not-too-distant future when houses and buildings outfitted with the proper equipment would be able gather electric energy stored in humidity in the atmosphere that could be used to fill a community’s electrical needs.

The concept isn’t new; electrical wunderkind Nikola Tesla had a similar idea more than a century ago.

Science has long sought the answer to how electricity builds up and discharges in the atmosphere, and whether the moisture in the atmosphere could even hold an electrical charge. But Fernando Galembeck, a professor at Brazil’s University of Campinas, claims he and his research team have successfully shown that it can, and by using special metal conduits to collect that electricity, it could allow homeowners and building managers to gather and store the electricity as an alternative energy source.

”Just as solar energy could free some households from paying electric bills, this promising new energy source could have a similar effect,” Galembeck said. He terms the new method “hygroelectricity” which means “humidity electricity”. Galembeck's research could also add to our understanding of how thunderstorms form.

In their laboratory experiments, Galembeck’s research team created a simulated atmosphere densely saturated with water (humidity), which they seeded with silica and aluminum phosphate, two chemical compounds commonly found in air. As water droplets formed around the tiny, airborne chemical substances, the researchers noticed the silica took on a negative charge while the aluminum phosphate droplets held a positive charge. The charged water vapor readily condenses upon contact with surfaces such as a cold can of soda or beer, and on the windows of air-conditioned buildings or vehicles. In the process, energy is transferred onto the contact surface.

“This was clear evidence that water in the atmosphere can accumulate electrical charges and transfer them to other materials it comes in contact with,” Galembeck said.

Just as solar panels convert energy from sunlight into a usable power source, the researchers think water vapor in the atmosphere could someday be harvested for its hygroelectric energy. The rooftops of buildings in regions of high humidity and thunderstorm activity could someday be fitted with special hygroelectric panels that would absorb the charges built up in the humid atmosphere and funnel the energy to where it can be utilized, and at the same time reduce the risk of lightning forming and discharging. The technology would be best suited to regions of high humidity, such as the tropics or the eastern and southeastern U.S.

SOURCES
ScienceDaily story
Wired story
Green Diary story

Thunderstorm over Lake Harriet in Minneapolis; Could this be a new source of energy for the Upper Midwest?

Jul
15
2010

“…Welcome back, class. Please hand in your essays on the scientific fundamentals of phosphorus-driven eutrophication in the Gulf of Mexico, and note that our exam covering chapter eight, the Biogeochemistry of Acid Mine Drainage, will take place next Tuesday. Today we will be covering fluid bed catalytic oxidation, hazardous waste landfill leachates, and NIMBY. But, first, let’s take attendance: Bueller?... Bueller?... Bueller??”

Say what? “Nimby?” Girl, puh-lease! He just made that up… didn’t he??

It wasn’t long into my undergraduate stint as an Environmental Science major that I came across the word, “nimby.” Actually, it’s not a word at all. It’s an acronym, N.I.M.B.Y., standing for “Not In My BackYard,” that captures an important public attitude that affects environmental policymaking.

NIMBY explains many people’s attitude towards environmental policies, capturing sentiments like,

“That’s such a cool and important idea! As long as it’s not actually happening in my community, that is.”

“Whatever. I don’t care so long as I don’t have to see it everyday.”

NIMBY: Yuck.  Who wants to look out their bedroom window and see a mountain of trash?  Not these guys.
NIMBY: Yuck. Who wants to look out their bedroom window and see a mountain of trash? Not these guys.Courtesy The Voice of Eye

Think About It

Do you like having your trash removed from your home? Most everyone does. But, would you like having a landfill in your backyard? Almost nobody does. This is the classic example of NIMBY. Nearly everyone likes having their trash collected from their property and transported out of sight and smell, yet someone, somewhere has to live beside a mountain of trash. As long as we’re not the ones living across the street from the landfill, most of us are satisfied with this method of garbage disposal. The same idea goes for wastewater treatment facilities as well.

Another classic example is nuclear power. Some people support nuclear power as an inexpensive and “clean” alternative to fossil fuels like oil and natural gas. However, the construction, maintenance, and decommissioning of a nuclear power plant poses risks and creates radioactive waste. Whether or not you think the risks and waste production are acceptable consequences depends largely on your proximity to the plant and/or ultimate disposal site for the nuclear waste.

A recent example of NIMBY is occurring in California this summer as covered in Green, a New York Times blog. In a valley near Santa Clara, Martifer Renewables canceled their plan to build a hybrid solar power plant. Set on 640 acres of agricultural land, the plant was supposed to produce electricity by solar power during the day and biomass burning by night. How sweet is that?? A 24-hour source of renewable energy! The California utility PG&E thought it was a great idea too and signed a 20-year power purchase agreement for 106.8 megawatts, which became part of their energy portfolio. PG&E must obtain 20% of its electricity from renewable resources by December of this year and another 13% (for 33% total) by 2020, as mandated by California state energy goals. Now that the project is canceled, PG&E will have to look elsewhere for sources of renewable electricity or risk missing their mandated targets.

Regarding the canceled project, Martifer executive, Miguel Lobo, wrote in a June 17th letter that,

“We were not able at this time to resolve some of our issues regarding project economics and biomass supply amongst other things.”

What Lobo was likely referring to are the complaints of local residents and regulators who contested several aspects of the project. Chief amongst the complaints was the around-the-clock operation made possible by burning biomass. What exactly were they so excited about? Noise, waste, and air pollution – all realities of energy production, yet things we’d rather not experience ourselves. In short, NIMBY.

Alright, so what?

Now that I’ve opened your eyes to the existence of NIMBY, you might be wondering how it influences environmental policymaking. The easiest answer is that environmental policymakers seek to find a balance between the conflicting desires for new technology like this power plant and local opposition and the NIMBY attitude. Often both sides make compromises and projects move forward on a slightly different path than previously proposed. However, as in the California case of Martifer Renewables, occasionally a project is completely scrapped. Other times, the project proceeds as originally planned. Which of the outcomes occurs depends largely on the organization and influence of the local opposition. In turn, this often raises issues of environmental or eco-justice.

Clearly our modern society cannot exist without landfills or wastewater treatment facilities as smelly and unsightly as they may be. Whether or not nuclear or other renewable energy power plants are equally necessary today is debatable, but it’s not hard to imagine a future in which they will be. If no one agreed to have these facilities in their community, life as we know it would be very different. This begs the question: how do you think policymakers should balance the needs of society at large against the NIMBY attitude of locals?

Jul
05
2010

One oft-cited reason for the relatively small percentage of renewable energy produced in the U.S. (just 7% of our energy is renewable) is that when you have a fluctuating energy source such as sunlight or wind, you need a giant battery to store the excess for use during times of scarcity. Here's one example discussing wind. Perusing Popular Mechanics this afternoon, I came across two innovative new battery designs that could bring us much closer to wider use of renewable energies.

The first design wins points for style--Beacon Power, of Massachusetts, has been testing a battery made of flywheels that store energy as they spin.

The second battery isn't quite as sexy, but it's no less useful--Donald Sadoway at MIT is working on an all-liquid metal battery that could absorb electrical currents up to 10 times as strong as today's hi-tech batteries.

Pretty exciting stuff!

It's Friday, so it's time for a new Science Friday video.

Science Friday
Science FridayCourtesy Science Friday

How would you describe the size of a wind turbine? There's no right answer. Turbines come in different varieties tuned for different uses. Compare the 256-foot-tall Gamesa G87 turbines, found at Bear Creek Wind Park in Penn., with the mini turbines developed by Bergey Windpower in Norman, Okla. The scale of both may surprise you.

We all like free stuff, especially free food. It's not quite "free," but at the Crowne Plaza hotel in Denmark, guest can earn a $36 meal voucher simply by riding a stationary bike for 15 minutes. The gimmick is part of the hotel's sustainability campaign. A 15 minute bike ride generates 10 watt-hours of electricity (for reference, 60 watt-hours is necessary to run a standard 60-W bulb for an hour). Check out the full Popular Science article here.

Land required to produce some energy: Find out how much land you need to make some kilowatts with your favorite energy tech.
Land required to produce some energy: Find out how much land you need to make some kilowatts with your favorite energy tech.Courtesy Robert I. McDonald
Renewable energy is awesome! Do not read me wrong. However, there are many things to take into account when we think about a new energy technology like wind or ethanol. Like, how much land do we need to devote to producing that energy? A new study shows that some darlings of the renewable fuels set are pretty land intensive (NPR story on energy sprawl). What's the least land intensive? Reducing our consumption....gulp.

Jul
19
2009

Two cylinder Stirling engine: Alpha type Stirling engine. The expansion cylinder (red) is maintained at a high temperature while the compression cylinder (blue) is cooled. The passage between the two cylinders contains the regenerator.
Two cylinder Stirling engine: Alpha type Stirling engine. The expansion cylinder (red) is maintained at a high temperature while the compression cylinder (blue) is cooled. The passage between the two cylinders contains the regenerator.Courtesy Zephyris
Four newly designed solar power collection dishes called SunCatchers™ were unveiled at Sandia's National Solar Thermal Test Facility. The new dishes are the next-generation model of the original SunCatcher system. Designed for high-volume production, ease of maintenance, and cost reductions, the dishes could be in commercial service by 2010. The projects are expected to produce 1,000 MW by the end of 2012. One megawatt powers about 800 homes.

Better and cheaper solar conversion

SunCatcher™ power system
SunCatcher™ power systemCourtesy Randy Montoya
Last year one of the original SunCatchers set a new solar-to-grid system conversion efficiency record by achieving a 31.25 percent net efficiency rate, toppling the old 1984 record of 29.4.

Source: New SunCatcher™ power system unveiled at National Solar Thermal Test Facility, Sandia News release.

Jun
01
2009

Wind turbines surfin' the deep blue sea
Wind turbines surfin' the deep blue seaCourtesy Flickr
Last week, I was lucky enough to partake in a fun-filled road trip to Colorado. Though the Rocky Mountains are a spectacular site, I found myself more excited to see all of the wind turbines on the 15-hour drive from Minneapolis to Colorado Springs. This ultimately resulted in a research extravaganza, as I wanted to know more about how wind energy works and what the US was doing to improve renewable energy.

Lets start with a few Minnesota wind facts :
• Total installed wind energy capacity is currently 1752.16 megawatts
• Total wind energy potential is 657 billions of kWh/year
• Currently ranked at 4th in US for current wind energy output (Go Minnesota!)

On average, one household will consume around 4,250 kilowatt-hours per year , so think of how many homes can be powered if Minnesota was reaching its wind energy potential.

I also came across this article that came out today in Scientific American that discusses the great steps that Hawaii is taking towards renewable energy. Recently, Hawaii signed an agreement with the US Department of Energy (DoE) that outlines a plan to obtain 70 percent of its power from clean energy by 2030, in which 40 percent will be from renewables like wind farms.

As of right now, the state relies on imported oil for 90 percent of its power. If a man-made or natural disaster were to occur that would prevent shipment of oil, Hawaii cannot plug into the mainland’s electrical grid, making them extremely vulnerable. So not only will they gain energy security, but the cost of electricity will also lower by reducing the amount of money spent on shipping money to foreign countries for oil (10% GDP).

The largest source of renewable energy will be makani, or wind. There are currently two proposed farms for Lanai and Molokai islands that will together generate a total of 400 megawatts of electricity, which will provide 25 percent of Oahu’s total generation capacity. Considering that over 70 percent of the stat’s population lives in Oahu, that’s a lot of energy! Solar water heating, geothermal energy, and the novel technologies in ocean thermal plants will also be used to provide the Hawaiian islands with clean, renewable energy.

For more information on what you can do here in Minnesota, check out this blog post from ARTiFactor that describes Windsource, a great program through Xcel Energy.