Rooftop Solar, more energy with less cost

A startup called TenKsolar, based in Minneapolis, says it can increase the amount of solar power generated on rooftops by 25 to 50 percent, and also reduce the overall cost of solar power by changing the way solar cells are wired together and adding inexpensive reflectors to gather more light.

The tenKsolar RAIS PV module with its ground-breaking Cell Optimizing technology is the only flat plate PV module capable of efficiently harvesting reflected light. Other solar panels depend on uniformly distributed light to balance the cells in the system. They can only make as much electricity as their least productive cell. This means that shading or adding extra light to a cell creates a problem for conventional panels. However, tenKsolar RAIS modules integrate the light across the entire module surface and turn it into power. Because of proprietary Cell Optimizing internal to the module, spots of shade, soiling, even physical damage to a portion of a module will have minimal impact on the individual module or array output.
In addition to the gains made by added light, a tenKsolar system operating in real-world conditions converts module power to grid electricity at about 92% efficiency, as compared to conventional solar at less than 80%. By decoupling internal cell dependencies to ensure cells are operating at their intrinsic MPPT under all environmental and lighting conditions (versus overall module MPPT), a tenKsolar system increases inverter efficiencies, tolerances to non-uniform soiling, improves system availability and reduces annual degradation. No other architecture including micro-inverters nor external DC optimizers – is competitive with the system level optimization of the RAIS architecture and Cell Optimizing design of the RAIS module.

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Renewable energy for computation

Researchers at Cambridge University want to put data centers in places so remote they aren't on any power grid. Their models indicate that moving data-hungry computation to places such as scorching deserts, windswept peaks, and the middle of the Atlantic Ocean—all rich in sunlight and wind energy—could allow this otherwise unharvestable energy to do useful work.

In a paper to be delivered at the 13th annual HotOS conference in May, the authors offer an extreme model of how cloud services could incorporate remote data centers powered only by renewable energy. Their scenario sites one solar- and wind-powered data center in the desert of southwest Australia and a second one in Egypt, on other side of the planet. This placement is no accident: putting them in different hemispheres, on opposite sides of the earth, maximizes the solar and wind energy they can harvest.
One catalyst for such a radical rethinking of how data centers can be sited and powered is the increasing availability of advanced fiber-optic networks.  Connecting a remote renewable-energy plant to a power grid remains prohibitively expensive, reasoned the researchers working on this project—Sherif Akoush, Ripduman Sohan, Andrew Rice, Andrew W. Moore, and Andy Hopper—but running fiber-optic cable to such a plant would be relatively easy and cheap.
"We envisage data centers being put in places where renewable energy is being produced and you could never economically bring it back to heat a house," says Andy Hopper, senior author on the paper and head of Cambridge University's computer science department. "But you could lay a fiber and use energy that is otherwise lost, in that it's not economically transportable." One way to think of the underlying principle, he notes, is that it's easier to move bits (made up of photons) than electrons.
Jonathan Koomey, a researcher and consulting professor at Stanford, cautions that a number of real-world factors could render the Cambridge team's hypotheticals invalid. While data centers are costly, Koomey explains, the value they create is so far in excess of those costs that anything that reduces their effectiveness would reduce their net benefit to society.
"If the actions you take to save costs would also cut into the number of computations that you can then deliver, you'll reduce economic benefits from data centers, and that's presumably not what the authors had in mind," says Koomey.
Hopper, however, points out that the larger effort of which this paper is a part—the Computing for the Future of the Planet project—takes it as a given that more computing is always good, because the virtualization of goods and services displaces more energy-intensive activities in the physical world. He says that a system like the one he proposes would be implemented only at either "no cost to overall performance [of a cloud computing system] or at an attractive cost to performance."

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Greening the Fleet

ALTe Powertrain Technologies, the Michigan developer of a range extended electric powertrain, has signed a Letter of Intent (LOI) to form a joint venture with Inmatech, Inc., a leading developer of advanced supercapacitors, to produce and sell hybrid electric storage (HES) devices composed of batteries, supercapacitors and control electronics. The blend of supercapacitors with lithium ion battery cells will enable longer life for the battery cells while reducing cost by as much as 40% for an equivalent size battery composed exclusively of lithium ion cells. The applications will range from automotive batteries to stationary grid power leveling devices.

To assist in bringing the HEV devices to market, ALTe and Inmatech have submitted grant applications through various federal funding agencies including the Department of Energy. Initial feedback has been very positive and the projects are now being evaluated by government technical specialist teams. Should the grants receive final approval, the JV will be able to accelerate product development and production operations to facilitate sales in early 2014.
“We are very pleased to be entering into a relationship with Inmatech, as we will be able to provide the best battery solution for our customers while opening new opportunities to expand our business to further supply the automotive industry’s growing need for advanced electric powertrain equipment,” said ALTe Founder, Chairman and CEO, John D. Thomas. “We view this initial response from the Department of Energy as an important testament to the potential of this relationship and the value of the technology we are developing,” he said.
Stefan Heinemann, President & CEO of Inmatech, declared “ I am thrilled to launch into the JV with ALTe as it will accelerate our plans to bring this novel material based supercapacitor to market, offering dramatic cost savings to the industry with very high energy density.”
ALTe’s Range Extended Electric Powertrain will replace standard V-8 engines, retrofitting into existing fleet vehicles as well as in “glider” applications of new vehicles to increase their fuel economy by up to 200% and lower emissions. Most recently, ALTe announced a partnership with Manheim, the world’s leading automotive reselling service, to create installation centers for fleet conversions across the country.
The company will be announcing its first fleet customers in the coming months, and ALTe’s electric powertrain system will be installed in commercial and government fleets beginning next year.
About ALTe:
ALTe is the developer of a Range Extended Electric Powertrain used to repower light commercial vehicles up to 26,000 GVW. The system will retrofit into existing fleet vehicles as well as in “glider” applications of new vehicles to dramatically increase their fuel economy and lower emissions. Designed to replace a base V-8 internal combustion engine powertrain, the system’s patented technology improves fuel economy from 80% to 200%. Based in Auburn Hills, Michigan, the company is headquartered in an 185,000 square foot facility where it will assemble its powertrain kit that will be shipped to installation locations across North America

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Lend To Carbon-Cutting Entrepreneurs With Kiva's New Green Loan Program

Chances are, you've at least heard of Kiva, the microfinancing nonprofit that allows users to give bite-sized loans to entrepreneurs in poverty-stricken regions. Because people like to feel good by offering cash to worthy causes (or so we've heard), Kiva has done exceptionally well, funding $200 million worth of microloans since its launch in 2004. And as of today, you can specifically fund what are, in our opinion, the smartest entrepreneurs--the ones who realize that efficiency is the key to becoming self-sufficient. It's called Kiva Green Loans.

There are two pieces of the new Green Loans category: lenders can now click on the Green Loans box on Kiva's "Lend" page to find entrepreneurs who want money for a myriad of efficiency-related efforts (i.e. creating organic fertilizer, buying renewable energy-generating devices, and converting vehicles to run on electricity or biofuels), and Kiva's field partners--the microfinancing institutions that partner with the site--will be allowed to raise more money on Kiva if they provide loans for energy-efficient technology.
"When we talk to people [about switching to energy-efficient technologies], one of the issues is financing.  More people might buy a Prius if the financing is 0% APR. It's the same kind of dynamic that plays out with low income households," explains Premal Shah, President of Kiva.org.
One of the 60 entrepreneurs that debuted in the Green Loans section today is Andrew Kipsang, a Kenyan businessman who leases Solio solar chargers to members of his rural community. He has been nicknamed "Bwana Stima," or Mr. Electricity. Another is Maylen Parisan, a Filipina food vendor who wants a solar lantern to cut fuel costs and extend her working hours.
There are a number of reasons why these kinds of loans make sense. "The Internet community is willing to channel money, it's just more patient, lower-cost, and risk-tolerant capital," says Shah. "If the Internet funds [Green Loans] quickly, it will send a signal that there is demand to fund loans in this category which will in turn change behavior around the world."
That's a good thing--pollutants from dirty fuels (i.e. charcoal and kerosene, which are commonly used indoors) are responsible for killing over a million people each year. On a more selfish note, encouraging entrepreneurs in the developing world to switch to clean fuels cuts down on carbon emissions, which is great news for carbon-hungry nations like the U.S. We can't afford other countries spewing emissions at the same rate as us.

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Battery Harvests the Energy of Estuaries

Renewable energy exists in the most unusual places. For example, in coastal estuaries, where fresh water rivers meet up with saltwater seas, the difference in salinty can represent about a kilowatt of free energy for every liter of water.
Scientists in Standford University's Department of Materials Science and Engineering have developed a new battery that taps into that electrochemical energy. The team says their "mixing entropy battery" could potentially supply 13 percent of the world's energy needs.

The battery itself is quite simple, consisting of one positive and one negative electrode. The idea is to alternately flush river water and sea water through the battery. Both kinds of water contain charged particles called ions, but seawater contains 60 to 100 times more ions than freshwater. When freshwater and its ions are flushed out and replaced with seawater, the battery produces a charge. The scientists estimate that a power plant built near an estuary could potentially produce up to 100 megawatts.
The scientists state the mixing entropy battery's simple fabrication offers a practical solution and shows potential as a future source of renewable energy. The process for generating electrical energy can also be reversed to remove salt from sea water to produce drinking water. Currently the team is modifying the battery for commercial use.

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MIT Researchers Use Viruses To Build More Efficient Solar Panels

Teams of viruses can help build better solar panels by ensuring nanoscale components behave properly, according to a new study. MIT researchers say their virus-assisted breakthrough could improve solar panels’ energy conversion efficiency by one-third.

Scientists already knew that carbon nanotubes, rolled-up sheets of graphene, could improve the efficiency of photovoltaic cells. Ideally, the nanotubes would gather more electrons that are kicked up from the surface of a PV cell, allowing a greater number of electrons to be used to produce a current.
But there are complications — carbon nanotubes come in two varieties, functioning either as semiconductors or wires, and they each behave differently. They also tend to clump together, which makes them less effective at gathering up their own electrons. MIT researchers found that a certain bacteria-attacking virus called M13 can be used to make things go more smoothly.
M13 has peptides that bind to the carbon nanotubes, keeping them in place, MIT News explains. Each virus can grip about five to 10 nanotubes each, using roughly 300 of the protein molecules. The viruses were also genetically engineered to produce a layer of titanium dioxide, which happens to be the key ingredient in Grätzel cells, a.k.a. dye-sensitized solar cells. (These cells use TiO2 instead of silicon, and their inventor, Michael Grätzel of the École Polytechnique Fédérale de Lausanne, won the Millenium Technology Prize for them last year.) This close contact between TiO2 nanoparticles helps transport the electrons more efficiently.
The viruses also make the nanotubes water-soluble, which could make them easier to incorporate into PV cells at room temperature, lowering manufacturing costs.
Graduate students Xiangnan Dang and Hyunjung Yi, MIT professor Angela Belcher and colleagues tested this method with Grätzel cells, but they say the technique could be used to build other virus-augmented solar cells, including quantum-dot and organic solar cells.
They also learned that the two flavors of nanotubes have different effects on solar cell efficiency — something that had not been demonstrated before. Semiconducting nanotubes can enhance solar cells’ performance, but the continuously conducting wires had the opposite effect. This knowledge could be useful for designing more efficient nanoscale batteries, piezoelectrics or other power-related materials.
The virus-built structures enhanced the solar cells’ power conversion efficiency to 10.6 percent from 8 percent, according to MIT News. That’s about a one-third improvement, using a viral system that makes up just 0.1 percent of the cells’ weight.

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