Archive for the 'solar' Category

Google’s Solar Trees are Thriving

Published
by
greenhl
on June 1, 2008
in action, corporate, energy and solar
. 0 Comments

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Okay, Google hasn’t really unlocked the genetic secret to grow solar trees (I’m sure they will soon), but their solar installation is really like a solar forest. In a previous post, I wrote about how Google gave its employees a lift with the Google Shuttle Program. The program brings hundreds of workers to and from its offices each day, and in the process, removes hundreds of cars from the roads.

I recently discovered another great Google initiative, the Google Solar Project, which “went live” last year. In October 2006, Google announced an initiative to install over 9,200 solar panels in its Mountain View campus, nicknamed the “Googleplex”. The solar panels are installed everywhere from the top of their buildings to their parking lots. In fact, one great side benefit of the solar arrays is that a huge amount of covered parking was produced. I wonder how much energy is saved for employees who don’t have to use their air conditioning because their cars were not baking under the sun all day?

Google’s solar array went live last year and produces an estimated 1.6 megawatts of electricity, enough to power about 1,000 homes. The undertaking was immense and is one of the largest corporate installations at the time (and it is still one of the largest corporate installations). To understand the scale of electricity produced, the panels are expected to offset approximately 30% of Google’s peak electricity consumption at those buildings. Although the return on investment is estimated to be between 5 – 10 years, Google undertook this project to help fulfill its role as a responsible corporate citizen, something more companies and people should aim to do. Not only is Google saving electricity, but they are also saving money and using this as a working lab to demonstrate the feasibility of large solar installations.

Although installing a solar array can be fairly expensive and not an option for many people, it’s great to see companies like Google stepping up to do its part. Many other companies have already installed solar arrays, and many more are beginning to do so. I do have one question. Who gets the fun job of cleaning all these solar panels?

Storing Solar Energy – and we’re not talking about giant flywheels, guys.

Published
by
Paul
on April 23, 2008
in energy and solar
. 1 Comment

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Maybe it’s because I am a mechanical engineer by training, and I always think in terms of mechanical mechanisms, but whenever I think of storing solar power, I think of a giant flywheel. Spinning and spinning. That’s what you all think of too, right?

Well, it turns out that that’s just not right, and it’s the New York Times that sets me straight. Last week they had a fascinating article that talks about how the new solar utility facilities are using giant tanks of molten SALT to store heat energy generated by thermal solar plants during the day, for use when clouds pass overhead, or at night. Did you even know that salt melts?

These technologies and techniques are truly fascinating because they get one of the obstacles which prevent us from exploiting the almost limitless solar energy that we receive every day.

Wal-Mart’s big scale means huge environmental impacts

Published
by
greenhl
on April 16, 2008
in action, corporate, recycling and solar
. 7 Comments

walmart_solar_array walmart_hybrid_diesel_truck

To understand the positive environmental impacts Wal-Mart can make, it’s important to first understand Wal-Mart’s massive scale. We all know Wal-Mart is “big”, but here are some Wal-Mart numbers to help put things into perspective.

  • Over 4,100 stores in the US and another 3,125 internationally for a total of over 7,200 stores globally
  • Saw nearly $350 billion in revenue for the last fiscal year and over $100 billion in this past 4th quarter
  • Visited by over 100 million shoppers each week (that’s only counting America)
  • Employs over 1.9 million people
  • Accounts for 8 percent of retail sales in the U.S. (excluding automobiles)

As we can see, anything Wal-Mart does is simply huge. One thing Wal-Mart has done well is experiment with energy saving techniques such as solar power, wind power, new HVAC technologies, waterless urinals, and new lighting technologies. In 2005, Wal-Mart opened two experimental supercenter stores in McKinney, Texas and Aurora, Colorado. These stores employ the latest technologies and use 20% less energy than the standard baseline superstore. They are platforms for a lot of the technology rolled out to their other stores. In January 2008, Wal-Mart opened a second high-efficiency store, which employs state-of-the-art technologies to use 25% less energy than standard stores. They employ technology such as water reclamation, waterless urinals, and intelligent lighting sensitive to time of day and store traffic. As some of this technology is rolled out to their other stores, efficiencies and energy savings will really add up quickly.

Wal-Mart is employing solar technology in 22 of its Hawaii and California stores. These stores generate 30 percent of the power needed to operate a store, or over 20 million Kilowatt hours of energy per year. This helps reduce greenhouse gases 6,500 – 10,000 metric tons per year.

In 2006, Wal-Mart installed high efficiency auxiliary power units on all trucks that make overnight trips, allowing drivers to turn off their truck engines during breaks. The annual impact is estimated to be 100,000 metric tons of carbon dioxide emissions and a savings of 10 million gallons of diesel fuel. Also, the company estimates it will save $25 million per year. In addition, Wal-Mart is working to convert its entire fleet of trucks to hybrid diesel technology by 2010 and to double the fuel efficiency of its fleet within 10 years.

By May of this year, Wal-Mart plans to only sell concentrated liquid laundry detergent in all its U.S. stores and Sam’s Clubs. Although this may sound like a small change, reduced packaging and water needs will save an estimated 400 million gallons of water, 125 million pounds of cardboard, and 95 million pounds of plastic resin. There are also huge transportation reductions and savings.

On October 3, 2007, Wal-Mart sold its 100th million compact florescent light bulbs. Each CFL saves $30 in utility costs, uses 70 percent less energy than a traditional light bulb, and prevents 450 pounds of greenhouse gases from being released into the atmosphere. Multiply these benefits by 100 million, and you can see the impact add up quickly.

Wal-Mart also started selling reusable plastic bags for $1 in its stores. If Wal-Mart sells its projected 2 million bags, Wal-Mart will have avoided producing 100 million disposable plastic bags. This is equivalent to 1,185,000 pounds of plastic resin.

Again, the cynic in me says that Wal-Mart is likely taking these actions to increase their bottom line or to create some good press. However, whether or not we are personal fans of Wal-Mart, the fact is Wal-Mart is taking action, and they are making a huge, noticeable difference. In the next and final article, we’ll discuss how Wal-Mart is working with suppliers to increase efficiencies beyond its own stores.

Solar could solve all of our energy problems. Eventually.

Published
by
Paul
on April 9, 2008
in energy and solar
. 2 Comments

solar.jpgIt seems to me that alot of the smart money in energy these days is in solar. And it’s no wonder. I was listening to a really interesting Science Friday podcast on solar energy and Ira Flatow mentioned a really amazing fact – that if you built a solar energy plant that captured the solar energy that hits a 100 x 100 mile square in the desert, you could generate enough electricity to supply the entire U.S. Amazing.

I did just a bit of digging, and found a few other amazing tidbits:

  • Capturing 0.02% of the solar energy that hits the earth could supply ALL of our energy needs. (Wikipedia)
  • There is 10,000 times more sunlight than we need to meet 100 percent of our energy needs (scientist Ray Kurtzweil)

Of course, there are major problems that need to be resolved, including how to capture that energy, the fact that solar is mostly available during the day, and transport issues, but they really seem solvable.

We’re going to be posting more about this topic in the coming months, but in the meantime, take a look at the Science Friday page, or listen to their podcast. It’s really encouraging!

GRID Alternatives

Published
by
JB
on February 6, 2008
in energy, household and solar
. 0 Comments

GRID AlternativesIf you live in the Bay Area and are interested in delivering efficient forms of energy to low income home owners, consider volunteering for Oakland-based GRID Alternatives.

According to their website, “[GRID Alternatives has] installed 151 solar electric systems for low-income families throughout Northern and Southern California. These systems are reducing each family’s electric bills by approximately 75%, which will translate to a total of over $2.49 million in energy cost savings over the systems’ projected life spans. They will also prevent roughly 7,555 tons of greenhouse gas emissions over the next 30 years, the equivalent of planting 10,544 trees.”

Great stuff. But there’s also a benefit to you, as a volunteer. You’re making a meaningful impact on your community as well as the environment, and you’ll pick up cool, hands-on solar electric installation experience.