Posts Tagged ‘energy efficiency’
Automatic Streetlamps Switch On When Cars Pass, Switch Off When Traffic Ceases
Researchers at the Institut Teknologi Bandung in Indonesia built a that recognizes a toy car speeding past, and switches on automatically. Jakarta, the massive megacity at which this effort is aimed, has more than 200,000 street lights, which cost about $17 million to operate in 2007, according to their study.
Researchers Suprijadi, Thomas Muliawan and Sparisoma Viridi built a prototype automatic lighting system that consists of a video camera, a lamp, a PC and a toy car. The camera, shooting at 25 frames per second, captures a car and the computer processes the image to determine whether it’s really a car.
The system recognized the passing toy car 91 percent of the time at speeds up to 2 mph, according to the paper, posted to the arXiv database and reported by Technology Review. The system’s accuracy falls as the speeds increase, however.
There’s plenty more work to be done to improve the system’s sensitivity, as well as test how it would react to pedestrians and cyclists, and how it works in different types of weather. But it’s a good first step toward a more efficient system for lighting the streets, as Tech Review points out.
A system like this could help reduce energy consumption in cities throughout the world. Then we won’t have to worry about injecting trees with .
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With New Materials, Air Conditioners Can Be Powered By Waste Heat
Adsorption chillers are a type of air conditioner that runs on waste heat, requiring very little electricity. But they’re big and expensive, which has limited their use to large, hot places like power plants or industrial spaces, as .
PNNL received a $2.54 million grant last summer from the DOE’s Advanced Research Projects Agency, ARPA-E, to build based on PNNL-developed nanostructured metal-organic heat carriers, or MOHCs. The material is more porous than existing adsorption materials, which makes them more efficient. PNNL researchers displayed the new material at a recent conference.
Adsorption is the binding of molecules or particles to a surface. In an adsorption chiller, hot water drives the cooling process instead of electricity. An evaporated refrigerant (in this case, water) binds to the surface of silica gel. The gel acts as a sponge for water vapor, and when the gel is heated, the water molecules are released, condensing into water droplets when the pressure rises.
The nanostructured MOHCs are even better sponges, trapping three or four times more water by weight, which can reduce the size of the system. They are also more efficient at releasing the water molecules, further reducing the chiller’s size; Tech Review gives the .
PNNL says a variety of heat sources can be used to warm up the MOHCs and free the water vapor, such as burning natural gas or other fuels, heating with solar thermal, or capturing engine or fuel cell system waste heat.
The research is funded by ARPA-E’s (BEETIT) project.
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How the Empire State Building Is Pioneering the Future of Energy Efficiency
Greening the world’s most iconic skyscraper
Now, a sweeping $13.4 million energy retrofit is slashing the Empire State Building’s energy consumption by nearly 40 percent and reducing greenhouse gas emissions by 105,000 metric tons over the next 15 years while trimming $4.4 million from annual energy costs. We took a firsthand look at what such a massive and meaningful project looks like, starting in a nondescript corner of the fifth floor where the Empire State Building is turning two-decade-old glass into future dollars.
Click to launch the photo gallery
It’s here that 100 double-pane windows per day are ripped from their aging frames, put through a rigorous cleaning process, treated with a thin UV-resistant film, and pumped full of pressurized argon and krypton gasses that improve their insulation values. By the time the retrofit is complete, all 6,514 windows will have been refurbished at a cost more than $1,600 per window less expensive than replacing them would be.
The window rehab – and other projects like it – reduces the energy load on the building, which in turn allows the engineers behind the retrofit to find efficiencies elsewhere. It’s all part of an 8-point plan that will eventually reduce the building’s energy consumption by 38.4 percent and its expenses by a few million dollars each year. With a footprint the size of the Empire State Building’s, that’s game-changing not just for the building, but also for the city and the world.
“Eighty percent of the energy consumed in New York City is consumed by buildings,” says Malkin, who is president of Malkin Holdings, part-owner of the Empire State Building. “Not by cars, not by buses, not by taxis, not by subways, not by trains. Even more interestingly, 20 percent of the buildings consume 80 percent of that energy. So 64 percent of all energy consumed in New York City is consumed by 20 percent of the buildings. That really took me by surprise.”
The Empire State Building fell into that energy-sucking 20 percent, so perhaps it was no surprise that the Clinton Climate Initiative took an interest in the building. In 2007, a representative for CCI approached Malkin seeking a building in which to demonstrate the foundation’s green retrofit program. Malkin was in the midst of a massive renovation project spanning his company’s entire portfolio, so he offered up a building at Broadway and 35th street in Midtown Manhattan.
The CCI pressed for something bigger. If it could turn the world-renowned Empire State into a model for efficiency, the whole world would take notice. At the time, the Empire State Building consumed the same amount of energy as 40,000 single-family homes, a figure that is unfortunately not unique; 43 percent of office space in New York City was constructed before the end of World War II, much of it comprising that 20 percent of buildings consuming the majority of the city’s energy. Greening the Empire State Building and skyscrapers like it wouldn’t just benefit real estate owners and their tenants; it would significantly move the dial on the entire city’s energy consumption.
Malkin agreed for reasons both altruistic and self-interested. “This is all about making money,” Malkin says bluntly of the retrofit. “To me, the whole concept of ‘green’ is a misnomer. The world is getting greenwashed. If you can’t prove it economically, it doesn’t matter.”
Malkin and the CCI set out to prove not only that enhanced energy efficiency is a cost-effective means of controlling expenses, but to create an economically feasible model that can be implemented by any building anywhere.
“If we succeeded only at the Empire State Building, we failed,” Malkin says. “It had to be broadly adoptable and malleable, and it had to be quantitative."
To create a cost-effective retrofit regimen, the project would have to be carefully managed. Malkin and the Empire State Building brought in technology and management experts from Johnson Controls and real estate consultants Jones Lang Lasalle, as well as the green-thinkers at the Rocky Mountain Institute, to craft a suite of technologies that not only incrementally reduce energy consumption but that have a multiplying effect on one another that generates further efficiency.
For Paul Rode, business development director for building efficiency at Johnson Controls, this synergistic effect was crucial. The retrofit team considered more than 60 off-the-shelf technologies and practices. They came up with eight initiatives that together were more effective than the sum of their parts. “If we take any one of these items out, the overall reduction values of the others change disproportionately,” he says.
The technology package attacks the problem from three sides. First, the team found ways to reduce the existing load on the building’s infrastructure by rehabbing the windows, installing better insulation behind the more than 6,500 radiators in the building and outfitting offices with occupancy sensors, better lighting controls, and layouts that maximize natural daylight. They also improved the efficiency of existing systems, retrofitting (rather than replacing) the chiller plant and replacing old air handling equipment with fewer and more efficient units.
The third component entails smartly controlling energy use. New York City’s tallest building is now home to America’s largest wireless control system. Carbon dioxide sensors throughout the building determine exactly how much outside air needs to be brought into the building at a given time, cutting down on unnecessary circulation, and occupancy sensors allow the building to better allocate air and manage lighting. And the Empire State's wireless thermostat sensors, unlike the hard-wired variety, can be moved around an office space to ensure they are placed where the temperature is average (rather than, say, tucked behind the copier or coffee machine where they record a falsely warm ambient temperature).
The same occupancy sensors that manage air allocation and lighting also tell the building’s management which offices are leaving the lights or the coffee maker on when no one is around. Offices are individually metered – and billed – and metering information is archived and provided to tenants online so they can see when and how they are using the most energy. That kind of meaningful information helps tenants manage thier behaviors to trim their own energy use – and expense. The Empire State Building's management is a partner in the entire process, helping each tenant figure out how it can reduce its load on the building.
“Tenants are drawn to us because tenants’ largest three expenses are salary, rent, and utilities,” Malkin says. “The ability to control expense is extremely important. The work that we are doing is not just from the perspective of our own building systems, but we’ve created a suite of services to help tenants achieve things that give them tremendous payback for their own spaces, their own investments.”
As for Malkin’s investment, he’s paying out $13.4 million incrementally for the retrofit, an investment that should save him $4.4 million per year. That means his capital investment in green tech will pay for itself in just three years, two years ahead of schedule. And by creating a competitive advantage for tenants, the building creates a monetary incentive for tenants to be conscious of their own energy consumption. Which, as Malkin is quick to point out, is how you really initiate change.
“It’s not just about doing the right thing for the sake of doing the right thing,” he says. “It’s about making money by doing the right thing.”
British Researchers Building Trial “Energy House” With Artificial Weather
Older homes have a certain charm, but they’re notoriously inefficient — they’re drafty, under-insulated, and equipped with old, energy-guzzling appliances. In an effort to study potential improvements, British researchers are building an “energy house” inside a that can generate rain, snow, wind and varying humidity levels.
By studying the different ways the house consumes energy, researchers hope to come up with ways to improve efficiency and reduce carbon dioxide emissions, BBC reports. The terrace-style home, designed by researchers at the University of Salford in Manchester, is thought to be the first of its kind in Europe.
Construction is only a few weeks in, but a of the house shows a sharp-looking brick building with nice bay windows, stylish bathroom sinks and energy-efficient appliances. It is designed to resemble the two-up, two-down terrace-style homes that make up about 15 percent of UK dwellings, . About 2 million Britons live in homes like that, which were mostly built prior to 1920.
The home’s snow globe shell can generate whatever conditions the researchers want, unlike other test properties that depend on Mother Nature.
In addition to creating the weather, the researchers will work with psychologists, health experts and sociologists to come up with sustainable solutions. They hope to study whether the use of certain colors and wall coverings affect how we perceive temperature; whether smart meters showing real-time energy use will affect behavior; and if game consoles like the Wii could be used to convert residents’ physical energy into a home power source, for instance.
The house is expected to be completed in February.
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Chicago Garage Fires Up Helical Wind Turbines for Attractive, Earth-Friendly Parking
This summer, 12 turbines started spinning at Greenway Self-Park, which bills itself, somewhat oxymoronically, as Chicago's first Earth-friendly parking garage.
Open-screen walls on the 11-story garage provide ventilation and reveal the cars inside, but also let passersby marvel at the turbines. The garage also has a cistern rain-collection system, sustainable building materials, a recycling program and an electric car charging station.
Lobbies on each floor include information about how to live more sustainably, and the garage has energy-efficient lighting. The garage is pursuing pursuing LEED certification from the U.S. Green Building Council. It even has a reversible meter that can measure and return power to Chicago's grid throughout the year.
Architect Todd Halamka, director of design at the Chicago office of HOK, tells Fast Company he wanted to celebrate the building's function, not hide it.
One wonders how green a parking garage can really be, but it's not like cars are going away anytime soon, so garages might as well aim to ameliorate their impact.
And at the very least, it adds to the architecturally interesting experience of parking in downtown Chicago -- you can go underneath trains, curl up through , and now this.
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Stanford’s New Solar Cells Are The First to Produce Electricity From Both Light and Heat
Exploiting both types of radiation could be the key to making solar power competitive with fossil fuels
Using readily available materials, a team of engineers has come up with the first solar technology to photovoltaic and thermal electricity generation.
Called "photon enhanced thermionic emission," or PETE, the process uses cesium to more than double existing systems' efficiency levels. PETE devices could be easily incorporated into existing solar collection systems, and they're cheap to boot.
Photovoltaic (PV) cells get less efficient as they get hot, which is one of the biggest problems in solar efficiency. What's worse, silicon -- used in most PV cells -- can only absorb energy from certain parts of the light spectrum. Ultimately, more than half the solar energy hitting each cell is wasted.
The Stanford system exploits the excess heat, turning it into extra electricity.
Researchers led by Nick Melosh, an associate professor of materials science and engineering, coated a piece of semiconducting material with a thin layer of cesium. This allowed the cell to use both light and heat to generate electricity, Melosh says.
The team used gallium nitride in the tests because it can withstand high temperatures, but PETE systems of the future would likely include gallium arsenide, commonly used in household electronics.
The system has to get extremely hot in order to work -- the hotter the better, Melosh says -- so new PETE systems will be a better fit for huge solar farms than rooftop arrays. They will need to include solar concentrators, but that creates another layer of efficiency, because less semiconducting material will be needed. Melosh says each device would require about a six-inch wafer of semiconducting material.
When used with the heat-conversion process, PETE devices could reach 60 percent efficiency, Melosh says. But as Stanford's news release points out, even 30 percent efficiency would bring solar power in line with the price of oil.
This video from Stanford further explains the process.
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In U.S. Senate, Climate Change Bill Dies With a Whimper
Democrats abandon hope of passing bipartisan bill this summer
Senate Majority Leader Harry Reid, who is seeking re-election this fall in Nevada, said, “We know that we don’t have the votes,” the reports.
The announcement is in stark contrast to senatorial optimism from a month ago, after Reid, Sen. John Kerry, D-Mass., and other senators met with President Obama at the White House. Back then, members of both parties expressed hope that they would reach a compromise sometime this summer.
But noticeably absent from that June meeting was Sen. Lindsey Graham, R-S.C., who had been working with Democrats on climate legislation. With their announcement Thursday, Democratic leaders seem to have abandoned hope of reaching a bipartisan compromise.
Democratic legislation called for a cap-and-trade system, in which a price is set for greenhouse gas emissions and polluters can pay for emissions credits. The House of Representatives passed a cap-and-trade bill last year, but Democrats who voted for it have faced a backlash, especially from utilities and energy firms.
Republicans backed their own climate change bill that included reductions in foreign oil imports and national energy consumption, but without cap-and-trade.
Now, the only legislation limping forward would raise fuel efficiency standards and ensure that BP pays for the spill in the Gulf of Mexico. The Times reports that the bill will also promote further production of natural gas and the manufacturing of natural gas vehicles, especially big trucks, a la T. Boone Pickens' . Pickens, a former oil magnate, advocates building wind farms across the U.S. to replace natural gas power plants, and using the natural gas to power the nation's long-haul trucks.
The bill would also tighten household energy efficiency requirements and increase financing of the Land and Water Conservation Fund.
Conservation groups are upset, lawmakers are unhappy and even utility executives are griping, because they'd hoped to see clear rules governing their companies' practices. In a rare feat, Congress seems to have frustrated everyone.
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