Tag Archives: green

Repair Cafes in The Netherlands

Repair Cafes in The Netherlands Give Life Back to Broken Objects

A new brand of DIY self-sufficiency is spreading across The Netherlands. Skilled craftswomen, mechanics, seamstresses, and handypersons are banding together to resist disposable consumer culture. It is the rise of the Repair Cafe, a place where neighbors get together to extend the life of their material belongings. “Fixers” mend clothes, restore furniture, rehabilitate electrical appliances, and enjoy each other’s company while industriously toiling away. The first cafe was founded by Martine Postma in Amsterdam in October of 2009. Today, there are 20 fully operational Repair Cafes, and 50 more in the planning stages.

I really like these efforts. We throw away too much stuff that has plenty of useful life left. Also it is a great way to build community. And it is an interesting way to learn about products we use everyday (both by fixing them and having your items fixed). The throw away culture is something we should aim to change. By these actions and also by engineers designing products to be fixed instead of thrown away. I donated to a similar fixer collective in Brooklyn via Kickstarter.

Google Lets Servers Stay Hot, Saving Air Conditioning Costs

The electricity to run huge server farms is enormous. One of the significant cost is air conditioning to cool down the server rooms.

Too Hot for Humans, But Google Servers Keep Humming

Google’s data center in Belgium, which was the company’s first facility to rely entirely upon fresh air for cooling, instead of energy-hungry chillers.
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For the vast majority of the year, the climate in Belgium is cool enough that this design works with no problems. When it gets hot in Belgium, the temperature inside Google’s data center warms beyond the facility’s desired operating range
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During these periods, the temperature inside the data center can rise above 95 degrees.
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“We’ve had very few excursion hours, and they don’t last long, so we let the site run right through them. We ask our employees to go in and do office work. It’s too warm for people, but the machines do just fine.”

Google’s experience is the latest affirmation that servers are much tougher than we think. Many data centers feel like meat lockers, as servers are maintained in cool environments to offset the heat thrown off by components inside the chassis. Typical temperature ranges in data centers often range from 68 and 72 degrees.

In recent years, rising power bills have prompted data center managers to try and reduce the amount of power used in cooling systems.

The temperatures in Fahrenheit obviously. I was surprised that the servers don’t seem to need to be chilled to perform well.

Mitsubishi Uses a Sled of Bubbles To Improve Ship Efficiency

Ship a riding sled of bubbles. Image from: CFD Predictions of Bubbly Flow around an Energy-saving Ship with Mitsubishi Air Lubrication System

Mitsubishi completed the conceptual design of a new container ship; this eco-ship achieves a 25% decrease in CO2 emissions over existing ships. Three, of these ships, with the Mitsubishi Air Lubrication System (MALS), are being built now (they should be completed in 2014).

In addition to blowers to create air bubbles under the vessel bottom, the three grain carriers will also feature a newly designed bow shape that will reduce wave-making resistances. For propulsion, the ship adopts a system to effectively convert the main engine power into propulsion power by positioning fins forward of the propellers and placing particular grooves in the propeller boss cap.

Using “eco-ships” to substantially reduce CO2 emissions from maritime transport

Reducing the frictional drag on the hull of a ship saves fuel and lowers CO2 emissions. To achieve this, MHI developed the Mitsubishi Air Lubrication System (MALS), which reduces frictional drag by introducing air bubbles by air blower into the water around the bottom of a ship’s hull, covering the ship in bubbles. By arranging the air blowhole location and shape and controlling the air volume, the lubrication effect has been enhanced, reducing CO2 emissions per container transportation by 10 percent.

This system has already been introduced on module carriers, and has been proven to reduce CO2 emissions significantly.

Using a Virus to Improve Solar-cell Efficiency Over 30%

Solar and wind energy are making great strides, and are already contributing significantly to providing relatively clean energy.

Researchers at MIT have found a way to make significant improvements to the power-conversion efficiency of solar cells by enlisting the services of tiny viruses to perform detailed assembly work at the microscopic level.

In a solar cell, sunlight hits a light-harvesting material, causing it to release electrons that can be harnessed to produce an electric current. The research, is based on findings that carbon nanotubes — microscopic, hollow cylinders of pure carbon — can enhance the efficiency of electron collection from a solar cell’s surface.

Previous attempts to use the nanotubes, however, had been thwarted by two problems. First, the making of carbon nanotubes generally produces a mix of two types, some of which act as semiconductors (sometimes allowing an electric current to flow, sometimes not) or metals (which act like wires, allowing current to flow easily). The new research, for the first time, showed that the effects of these two types tend to be different, because the semiconducting nanotubes can enhance the performance of solar cells, but the metallic ones have the opposite effect. Second, nanotubes tend to clump together, which reduces their effectiveness.

And that’s where viruses come to the rescue. Graduate students Xiangnan Dang and Hyunjung Yi — working with Angela Belcher, the W. M. Keck Professor of Energy, and several other researchers — found that a genetically engineered version of a virus called M13, which normally infects bacteria, can be used to control the arrangement of the nanotubes on a surface, keeping the tubes separate so they can’t short out the circuits, and keeping the tubes apart so they don’t clump.

The system the researchers tested used a type of solar cell known as dye-sensitized solar cells, a lightweight and inexpensive type where the active layer is composed of titanium dioxide, rather than the silicon used in conventional solar cells. But the same technique could be applied to other types as well, including quantum-dot and organic solar cells, the researchers say. In their tests, adding the virus-built structures enhanced the power conversion efficiency to 10.6% from 8% — almost a one-third improvement.

Read the full press release

How To Make Your Own Pesticide with Ingredients from Your Kitchen

Video by the Singapore National Park Board, on creating your own pesticide with just water, dish-washing liquid, chili, garlic and cooking oil.

Google Invests $168 million in Largest Solar Tower Power Project

Google is investing in a new solar tower power project located in California that will generate 392 gross MW of clean, solar energy. That’s the equivalent of taking more than 90,000 cars off the road. Google has now invested $250 million in clean energy.

Investing in the world’s largest solar power tower plant

works by using a field of mirrors, called heliostats, to concentrate the sun’s rays onto a solar receiver on top of a tower. The solar receiver generates steam, which then spins a traditional turbine and generator to make electricity. Power towers are very efficient because all those mirrors focus a tremendous amount of solar energy onto a small area to produce steam at high pressure and temperature (up to 1000 degrees F).
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Several large solar projects are in the works in the sunny Southwest (and around the globe), but Ivanpah will be the first solar power tower system of this scale. The Ivanpah Power Tower will be approximately 450 feet tall and will use 173,000 heliostats, each with two mirrors.

The Department of energy is also providing financing for this project. The project is 10 times larger than the largest solar photovoltaic project in California.

Appropriate Technology: Washing Clothes by Machine Instead by Hand

Hang Rosling provides great presentations exploring economics and human well being. I agree with his point that we should be thankful for economic and engineering progress that has freed us from menial tasks and allowed us to spend our time in higher value ways.

We need to remember (as he shows) there are many in the world that still do not enjoy these advances. For example, a majority of the world must hand wash their clothes. Engineers should continue to focus on the mass of humanity that needs fairly simple solutions.

He is also right that we need to find solutions to the extremely heavy use of fossil fuels by the rich countries. If the rich countries don’t reduce the pollution there will be great problems. And if the costs of clean energy are not decreased (which they should do) fast enough (which is the question), those that start to be able to afford the rich lifestyle, will add to the dangers we face economically and environmentally of continuing the unsustainable energy footprint the rich countries have been making.

Wave Disk Engine Could Increase Efficiency 5 Times

Norbert MÃ¼ller’s group has received $2.5 million from the U.S. Department of Energy Advanced Research Projects Agency-Energy (ARPA-E) in 2010 to build and develop the wave disk engine, which uses turbo combustion “shock wave” technology to convert either liquid fuel or compressed natural gas or hydrogen into electrical power. With this engine, fuel efficiency for hybrid vehicles could increase 5 times compared to internal combustion engine vehicles on the road today (and 3.5 times less than current hybrid cars), while reducing costs by 30%. The goal of MÃ¼ller’s team is to produce an engine that would give hybrid vehicles a 500-mile driving range and reduce carbon dioxide emissions by as much as 90%.

In the video he says they hope to have the engines in production vehicles within 3 years. My guess is he is being quite optimistic, but we will see. The new engine would allow 1,000 pounds to be removed from the weight of cars (by removing the need for drive train, radiator…).

Pepsi Bottles Made of Switch Grass and Other Plants

Pepsi bottles: no more plastic

The bottle is made from switch grass, pine bark, corn husks and other materials. Ultimately, Pepsi plans to also use orange peels, oat hulls, potato scraps and other leftovers from its food business. The new bottle looks, feels and protects the drink inside exactly the same as its current bottles, said Rocco Papalia, senior vice president of advanced research at PepsiCo.
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PepsiCo says it is the world’s first bottle of a common type of plastic called PET made entirely of plant materials. Coca-Cola Co. currently produces a bottle using 30 percent plant-based materials and recently estimated it would be several years before it has a 100 percent plant bottle that’s commercially viable.
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“This is the beginning of the end of petroleum-based plastics,” said Allen Hershkowitz, a senior scientist with the Natural Resources Defense Council and director of its waste management project. “When you have a company of this size making a commitment to a plant-based plastic, the market is going to respond.”

Coca-Cola said it welcomed other advances in packaging, but noted that it has scaled up use of its own plant-based bottle since introducing it in 2009. It also says it has demonstrated a 100 percent plant bottle in the lab and is still working to ensure it is commercially viable.

There are other plant-based plastics available or in development, but Herskowitz said these are not environmentally preferred because they typically use plants grown solely for that purpose rather than using the estimated 2 billion tons of agricultural waste produced each year. And these alternative plastics cannot be recycled.

Molten Salt Solar Reactor Approved by California

California has approved a molten salt solar reactor project. The plan is for a 150-megawatt solar power tower project. From the press release: the “Solar Energy Project has the ability to collect and store enough thermal energy each morning to operate at full power all afternoon and for up to 8 hours after sunset. The game-changing technology featuring inherent energy storage affords utilities with a generator that performs with the reliability and dispatchability of a conventional power generator without harmful emissions that are associated with burning coal, natural gas and oil.”

diagram of solar energy project using molton salt

molten salt solar system diagram

The heliostats focus concentrated sunlight on a receiver which sits on top of the tower. Within the receiver, the concentrated sunlight heats molten salt to over 1000 degrees Fahrenheit. The heated molten salt then flows into a thermal storage tank where it is stored, maintaining 98% thermal efficiency, and eventually pumped to a steam generator. The steam drives a standard turbine to generate electricity. This process, also known as the “Rankine cycle” is similar to a standard coal-fired power plant, except it is fueled by clean and free solar energy.

This is another green energy project that has a great deal of potential. There is a great need for such new energy sources and hopefully quite a few of these projects will let us enjoy a greener and more sustainable way to meet our future energy needs.

For those interested in the business aspects of this energy project: United Technologies provided SolarReserve with an exclusive worldwide license to develop projects using the proprietary molten salt power tower technology, which has been in development for nearly three decades.