Foamglas is an inorganic, high-compressive-strength insulation with no need for flame retardants or other hazardous chemicals. Photo: Pittsburgh Corning. Click on image to enlarge.

Read more...

Lake Mead, the nation's largest reservoir, which supplies 90% of Las Vegas's water and millions of other residents, shown at about half capacity in 2007. Ken Dewey photo. Click on image to enlarge.

Last week we examined the amount of energy it takes to transport and treat water--and how we can conserve energy by using less water. This week, we'll look at the inverse of that: how much water it takes to produce energy and how our energy conservation efforts reduce water use.

The water intensity of energy

Whenever water shortages loom anywhere, we hear about how much "embodied water" there is in various products. According to the Water Footprint Network, producing a slice of bread requires 11 gallons of water and producing a pound of beef takes 1,800 gallons. The same sort of analysis can be done with our energy sources. As with foods, different types of energy have different water intensities.

Electricity:

Read more...

GraniteCrete was used at Asilomar State Beach for durable, but natural-looking pathways and steps. Photo: GraniteCrete. Click on photo to enlarge.

Read more...

Niagara uses innovative "vacuum-assist" hydraulics to provide an effective, yet super-quiet flush in the Stealth toilet, requiring just 0.8 gallons. By using less water, this toilet saves energy. Photo: Niagara Conservation. Click on image to enlarge

It takes a lot of energy to transport and treat water in this country, and it takes a lot of water to produce the energy we use. To put this a different way: when we save water we save energy, and when we save energy we save water.

Most people don't think about this tight-knit relationship between energy and water, but public officials in a growing number of regions around the country are becoming quite aware of it. This week, I'll examine how much energy it takes to move water and to treat both supply water and wastewater. Next week, I'll look at how much water is used in producing our energy.

The energy intensity of water:

The amount of energy needed to deliver clean water and treat that water once we've used it varies tremendously by region. If you live in southern California, your drinking water is pumped either from the Colorado River and its assorted reservoirs (including the nation's largest, Lake Mead, which is now half empty) or from northern California. In either case, that water flows through hundreds-of-miles-long open aqueducts and, via pipelines, up and over mountain ranges.

Read more...

Previously a Burlington Coat Factory, the new community center at 45-51 Park Place, New York, will be a LEED certified space upon completion. Photo: Michael Appleton for The New York Times

The first mosque, in the world according to an article in The Daily Green, attempting LEED certification could be located in Lower Manhattan—in proximity of “Ground Zero”—the hallowed ground of the Twin Towers and 9/11. The proposed location of the new community center and mosque, Park51, has sparked controversy; some argue the location of Park51 is disrespectful. It should also be noted that Lower Manhattan is not very large and most buildings are in proximity to Ground Zero. And it’s difficult not to be excited about a project pursuing LEED certification, especially a community center.

Read more...

The Waterless Company's new residential Baja urinal begins shipping this week. Photo: Waterless Company. Click on image to enlarge.

Read more...

Streets in Copenhagen are designed to provide safe access for bicyclists. Photo: Alex Wilson. Click on image to enlarge.

1. Lighten the load. The more weight we haul around in our cars or trucks, the more energy we use. If you keep sandbags in the bed of your pick-up for winter traction, remove them in the summer. Empty your trunk of those unneeded items you've been hauling around.

2. Use air conditioning only when absolutely necessary. In some cars, running the A/C on max reduces mileage by as much as 25%. Around town, open a window. At highway speeds, it's usually better to keep windows closed to reduce aerodynamic drag. If the fan alone doesn't provide enough cooling, this is when the A/C makes sense.

Read more...

The Grundfos advanced, variable-speed, "smart" pumps for hydronic heating systems can reduce pumping energy use by 80%. Photo: Grundfos USA. Click on image to enlarge.

For the past couple years, I've been helping All Soul's Church in West Brattleboro, Vermont, save energy. While developing a plan to improve the performance of the building envelope of this early-1970s, heavily glazed and horribly inefficient building, one of our committee members found out about a grant program from the state that would support a heating system upgrade.

To make a long story short, we replaced the massive oil-fired boiler with a compact Buderus model that takes up just a fraction of the space; we got rid of the 6,000-gallon underground storage tank, replacing it with two 330-gallon tanks in the boiler room; we replaced the failed zone valves with new thermostatically controlled, electric zone valves; we stopped using the boiler to make hot water for three small lavatory sinks (for which the boiler would operate off-and-on all summer); and--the topic of this blog--we replaced the constant-speed, 1-horsepower (hp) pump with a high-tech pump from Denmark that should dramatically reduce the electricity we use for circulating hot water.

The pump we installed is a variable-speed Grundfos Magna with ECM motor and a unique AutoAdapt feature that uses an integrated logic board to "learn" the building's usage patterns and calibrate the pump operation accordingly.

Read more...

With careful driving techniques it's possible to significantly exceed the EPA mileage rating for any car. Source: U.S. EPA. Click on image to enlarge.

In this column I usually focus on how to save energy in our homes and businesses, but for many of us, getting around is our largest energy consumer--particularly in the summer months when we're not heating our houses. Some of us are lucky enough to have hybrid cars, and this gives us a head start in saving transportation energy. I just calculated that the 2003 Honda Civic Hybrid we own, which averages about 40 miles per gallon (mpg) year-round, has saved us about 2,800 gallons of gas over the 146,000 miles we've driven it (compared with a car getting the U.S. average of 22.5 mpg)--worth $7,000 with gasoline at $2.50 per gallon.

But for those who don't have a Toyota Prius, Honda Insight, or other hybrid, there are some simple ways to significantly reduce fuel consumption. It's easy to find tips for more efficient driving, but some of the more extreme strategies have come out of the hypermiling movement. In 2006, Wayne Gerdes coined the term "hypermiling" to describe the goal of exceeding the published EPA fuel economy ratings of cars--especially hybrids. Details of this practice can be found at Gerdes's website: CleanMPG.com.

Through hypermiling techniques, some hybrid car owners have been able to coax their mileage to over 100 mpg, and they compete with one another for boasting rights. Using the same techniques, drivers of conventional cars have been able to increase their fuel economy by as much as 50%--sometimes matching that of hybrid vehicles.

Read more...

This Bensonwood home in Alstead, New Hampshire, combines high-tech panelized construction and superb energy performance with simple elegance. Click on image to enlarge.

I had the good fortune last week to spend a few hours touring the Bensonwood offices and factory in Walpole, New Hampshire. I've known Tedd Benson for perhaps 20 years, and knew of him a lot longer than that through his writings. He pretty-much created the modern timber-framing profession, starting back in the early 1970s when he set out to reinvent the craft of timber-frame construction that our New England ancestors used centuries ago. His 1980 book, Building the Timber Frame House, and several others since, have inspired many of us for their vision, beauty, and rugged durability.

In recent years, Benson has shifted his primary focus away from timber framing (though that's still an important part of what his company, Bensonwood, is all about). His Open-Built® construction platform, inspired by the work of Open Building pioneer John Habraken and supported by MIT's Open Source Building Alliance, has gone a long way toward bringing down the costs of the top-quality homes his company builds.

Read more...