Affordable Housing Institute : US

Green is the new black, for three reasons identified by The Economist:
 

A green-home boom is getting under way, thanks to:

 

1.  Rising energy prices

 

And rising …

 

2.  New standards (the European Union’s Energy Performance of Buildings Directive, Britain’s Code for Sustainable Homes and California’s Green Building Standards Code, to name three recent examples), and

 

Not just a good idea …

 

… it’s now the law

 

3.  Improved technologies.

 

By a mixture of economics and social conscience, green is grabbing market share:

 

Many of these technologies have been around for a while, but they are now ready for the mainstream. In 2007 McGraw Hill Construction, a research firm, reported that 40% of all renovation in America included some green features, mostly windows and heating/cooling systems. The company predicts green homes will account for 10% of all building starts in America by 2010, with new green homes worth $20 billion in that year. When housing arises from its torpor, it could find itself transformed.

 

Where there is cost, there is innovation:

 

JEFF ROGERS welcomes visitors at the door of his newly renovated house, atop a sandy ridge on Cape Cod, Massachusetts. From outside the two-storey building seems unremarkable: its neat white trim, pale-yellow clapboard siding and shingle roof have been the local style for centuries.

But the house that Mr Rogers finished last year is anything but traditional.  It uses no fossil fuel and generates its own electricity.  

 

Rogers, keeping cool

 

As we’ll see, Mr. Rogers built his home as a demonstration, not an economic bench test, and the home is a good place to start, for, as Mr. Rogers’ company notes:

 

In the United States alone, buildings account for:

 

65% of electricity consumption,

36% of energy use,

30% of greenhouse gas emissions,

30% of raw materials use,

30% of waste output (136 million tons annually), and

12% of potable water consumption.

 

Breakthroughs in building science, technology, and operations are available to designers, builders, and owners who want to build green and maximize both economic and environmental performance. Source: www.usgbc.org

 

 

It contains few toxic materials—adhesives, paints and insulation are all free of formaldehyde and contain low levels of volatile organic compounds, and nothing in the house produces carbon monoxide.

 

Not just the President, he’s also a satisfied customer

 

Despite housing a family of four, the house uses less than a third of the typical amount of water, thanks to modern appliances, dual-flush toilets and low-flow taps and showers. A geothermal heat pump heats and cools the house using groundwater; even though it has no air conditioning, the house is cool in the Cape’s muggy summer heat.

 

Nice try, Economist, but Cape Cod is not muggy.

 

Sandy, yes; muggy, no

 

On the roof, photovoltaic solar panels sit next to arrays of water-heating tubes. Inside, the bright, warm lights recessed into the ceilings are low-energy light-emitting diodes (LEDs). Even the most traditional-looking elements are unusual: the roof shingles are made of recycled plastic and sawdust. This innocuous house on a quiet lane is, in fact, one of the greenest homes in America.

 

Not the cheapest, to be sure, for Mr. Rogers is no ordinary homeowner:

 

Although Mr Rogers runs a firm called New England Green Building, his house is within the budget of many homeowners.  It is typical of a new generation of green homes that have a dramatically reduced environmental impact, but do not require big changes in their inhabitants’ lives.

 

Mr Rogers says his 2,100-square-foot house—just under the average for new homes in America—cost $75,000, or 23%, more to build impeccably green than it would have otherwise.

 

Given that Mr. Rogers is a builder, I expect his total cost excludes his labor and probably that of his company.  He also had some meaningful financial help:

 

He expects to recoup [his net costs] in avoided energy costs within five years.

 

In energy consumption, payback is a tricky thing to calculate, depending as it does on both financing terms and energy prices:

 

Given the recent spike in energy prices, it may not take that long.

 

Or if energy pries fall, as they are now with the capital markets shakeout [$63 per barrel on October 25! – Ed.], it could take longer.

 

All we can predict is their unpredictability

 

However it’s determined, once the payback works, the network works.  And government can influence that payback dramatically, especially in the energy field, both through regulated energy prices, and with subsidies and tax credits:

 

He received $35,000 in rebates and incentives from state and federal governments.

 

Although purist economists shudder at the prospect of influencing markets through incentives, the fact (which causes the shudder) is that they work – incentives channel capitalism.

 

Must not be an economist

 

When there are non-economic externalities (like people’s desire to reduce their energy consumption out of concern for the planetary ecology), incentives have the effect of putting a number on the unquantifiable. 

The result, in recent years, has been a veritable explosion of improved technologies:

 

Electrochromic glass, with changeable opacity, is one new avenue of exploration. Some of the most promising is produced by a fir called Sage Electrochromics, based in Minnesota. Its product, which consists of sheets of glass with a metal-oxide coating, was first used in skylights in 2003. When a voltage is applied across the coating, the window darkens, allowing less light to enter but still permitting a view. America’s Department of Energy (which developed low-e coatings in the 1970s) has used this glass, along with an insulated sash, to develop a “zero-energy” window that saves more energy in reduced heating and lighting than it needs to operate.

 

Energy conservation will come, I think, through these auto-adjusting systems.

 

An even bigger leap may come from refining an older idea. Sheets of glass separated by a vacuum could bring windows’ insulating properties up to par with insulated walls, yet allow them to be nearly as thin as single panes of glass. The idea of vacuum-insulated panes has been around for nearly a century, and NSG/Pilkington, a Japanese firm that is one of the biggest glassmakers in the world, has sold such panes since 1996. But they remain a technical challenge: the difference in temperature causes the inner and outer sheets of glass to expand by different amounts, so that NSG/Pilkington’s windows can be used only where the temperature difference is less than 35ºC [for you Americans, that 63º, which means that if it's going to be 72 inside, it can't be colder than 10 outside], which rules out many homes in need of insulation.

 

Thermopane windows have been around for thirty years in affordable housing.  They almost always crack and fog.

 

 

Once the home has been duly sealed, the flow of air, moisture and heat in and out of it can be carefully controlled. Mr Rogers’s home features a heat-recovery ventilator—a device in his basement that filters incoming air and exchanges heat between incoming and outgoing air. Such devices can remove stale air from a home while retaining 85% of its heat.

 

Yes, but recall Padfield’s Law of construction complexity:

 

 

Steve Harris, a principal at ZEDfactory, an architectural firm based near London that designs green residences, prefers to use a special heat-exchanging wind cowl his company has developed. It uses no electricity, yet is able to recover 70% of the heat of outgoing air. The device, an angular scoop on the top of a home, has become a signature of the firm’s style, and will soon be commercialised for broader use.

 

Don’t laugh, they save money

 

The less precisely the technology has to be calibrated, the better.

 

The best-known green-home technology must surely be the compact-fluorescent light bulb, the very icon of green living.

 

We’ve all got used to seeing these, and seeing by these

 

Compact fluorescents use about one-third as much electricity as incandescent bulbs to produce the same amount of light.

 

High-precision in manufacturing, low-precision in maintenance – that’s the path to sustainability.

 

Yet the technology that will eventually eclipse it now makes economic sense, with the long-anticipated arrival of LEDs—a 40-year-old technology—in home lighting. But new LEDs use just 12% and can produce light of similar quality to warm halogen bulbs.

 

A bright future?

 

The classical incandescent bulb is horribly inefficient, pumping out much more heat than it does light.  Finding technologies that generate light efficiently, with minimal excess heat loss, holds the promise of vast energy savings.

 

With lifetimes measured in decades, they are a clear improvement over incandescent bulbs. “It’s the difference between a cellphone and the old rotary phones,” says Gary Trott, an executive at Cree, an LED manufacturer in North Carolina.

 

Some of us learned our dialing on these black beauties

 

Last year Cree began selling a dimmable LED version of common recessed ceiling fixtures. The firm estimates that under typical conditions, these lights could pay for themselves in five years, and save hundreds—or, where lights are left on more, thousands—of dollars over their lifespan.

 

The LED is poised to revolutionise the lighting industry. Philips, a big Dutch electronics firm which claims to have made one out of every four lights worldwide, says sales of LED lighting grew by 30% last year in an overall market that was worth €700m ($960m). Thanks to a string of acquisitions, its “green lighting” sales grew by 17% last year, with the strongest growth, tellingly, in home lighting.

 

There’s just one weak link to engineer: the wetware thermostat.

 

That’s what tax credits are for.

 

Reader, you are the weakest link: goodbye.

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