By Lawrence Ulrich , IEEE Spectrum , October 2010
http://spectrum.ieee.org/green-tech/advanced-cars/the-greening-of-the-supercar

Ferraris, just like Fords, must now conform to environmental regulations

Someday soon there will be an affordable and clever electric vehicle that will conquer the world, as the Model T and Volkswagen Beetle did in their day. In the meantime, there's the Tesla Roadster, a US $109 000, 300-horsepower, two-seat toy for rich, environmentally conscious gadget hounds. Yes, for every Nissan Leaf or Chevy Volt with mainstream pretensions, there's a battery-powered land rocket that's way more Bugatti than Beetle.

Makers of automobiles more associated with tearing up the earth than with saving it are suddenly rushing to outdo each other in the automotive industry's next big battleground: electric and plug-in hybrid cars. Their pitch is the familiar best of all worlds: cars that look hot, go fast, run clean, and consume either no gasoline or very little.

But really now, does a man who buys a six-figure missile on wheels really fret over fuel bills or global warming? Probably not, but carmakers say that affluent buyers increasingly want to make a green statement anyway. In a world where a fuel-sucking V-12 engine seems not just passé but nearly pathological, an electric sports car marks its owner as not just loaded but also progressive, ahead of the curve in both auto technology and fashion. Auto execs, of course, are only too happy to propagate this perception. "In the long run, we're either going to run out of oil or the price will go up dramatically," says Frank Van Meel, head of electromobility strategy for Audi. "There's a need to act right now."

And yet, it's not really the warming planet that's spurring the supercar makers. It's the heated rhetoric, and the forging of new government regulations. This is quite a change for a niche market that has obsessed over miles per hour while largely ignoring miles per gallon.

Under a controversial European Commission plan, new cars in Europe may be required by 2015 to meet a strict fleetwide average of 130 grams of carbon dioxide per kilometer driven. The United States is expected to adopt similar CO 2 standards and has already mandated a 22 percent improvement in fleet average fuel economy, to about 35 miles per gallon (6.7 liters per 100 kilometers) by 2016. Because CO 2 emissions are a remorseless function of how much fuel you burn, the EU target means that a gasoline car would need to consume just 5.1 L/100 km, or achieve 46 mpg.

There's just one problem: No conventional sports car in the world today achieves that kind of fuel economy or squeaky-clean emissions, let alone supercars like the 21.4 L/100 km (11 mpg) Lamborghini Murciélago, among the industry's worst offenders, belching 480 grams of CO 2 per kilometer. Even Lotus's tiny Elise, soon to be equipped with a shrimpy new 1.6-L four-banger, will emit 155 g/km. That's less than any current gas-driven sports car but still above the proposed target.

Small-scale sports-car builders such as Ferrari and Porsche have long been excused from meeting the United States' Corporate Average Fuel Economy rules. Other purveyors of power and luxury have paid fines for missing fuel-consumption standards, with Mercedes shelling out nearly $300 million since 1983-a practice the company has vowed to end by boosting efficiency.

Yet a fast-car fan might ask: In a world steaming with emissions from coal-fired power plants and hundreds of millions of cars, who cares if a Lamborghini guzzles gasoline more greedily than a Citroën? For years, sports-car makers have offered precisely that defense of their guzzling: These exclusive cars sell in such tiny quantities-and are driven so lightly, as weekend toys-that their environmental impact is negligible. Ferrari sells fewer than 10 000 new cars a year around the world, compared to the millions of a GM or Toyota. Ferrari officials say their exotic baubles tend to be driven less than 10 000 km a year on average, about half as much as a typical passenger car. Even so, regulations may limit the free passes and no longer allow major companies to buy indulgences for green sins.

Colin Peachey, Lotus's chief engineer, frankly allows that political and social forces are driving the industry. "In an ideal world, where burning fuel didn't damage the planet, there wouldn't be a case for electric cars. We'd carry on with our V-8s and V-12s and have all the performance and convenience that gas gives you."
It's hard to imagine a world in which wealthy car buyers can't have the cars they want-or one in which carmakers can't even make the cars they want. Peachey insists that sports-car builders could be effectively legislated out of existence if they don't hybridize or otherwise green their lineups. "The emissions may be a relative drop in the ocean, yet legislators are saying we're going to tax you until it hurts, and above a certain emissions level, you just won't be able to sell the car," he says.

The writing on the wall is even being translated into Italian: Ferrari has unveiled the 599 HY-KERS hybrid supercar concept, which combines a V-12 engine with an 80-kilowatt (107-horsepower) electric motor-and a 3-kilowatt-hour lithium battery said to be just 2.5 centimeters (1 inch) thick-boosting fuel efficiency to as much as 9.4 L/100 km (25 mpg) and reducing CO 2 emissions to 270 g/km.

The car adopts energy-capturing regenerative-braking technology from Ferrari's KERS (Kinetic Energy Recovery System, used in Formula One race cars), delivering an estimated 1.5 percent gain in fuel efficiency. And as if that weren't surprising enough to traditionalists, Ferrari chairman Luca di Montezemolo said recently that every car in Ferrari's lineup will adopt hybrid technology within three to five years. (Note to collectors: Now's the time to buy up the soon-to-be "classic" gas-burning models.)

Colin Chapman, the engineer, Formula One genius, and founder of Lotus, created the most enduring mantra of sports- and racing-car design: Add lightness. And for today's performance geniuses, electrified cars pose a tremendous challenge: how to reduce emissions and keep cars fast and razor sharp in handling-as customers demand-even as batteries and electric motors add weight and greatly complicate the pursuit of perfectly balanced (roughly 50-50) weight distribution between front and rear axles.

In a briefing on Ferrari's environmental issues, technical director Roberto Fedeli expressed confidence that the company would dramatically reduce CO 2 emissions while "keeping its soul" and honoring all its performance and fun-to-drive traditions. Yet further gains in engine efficiency won't be enough, he said. Ferraris and other models will begin to adopt the start-stop functions of hybrids, shutting engines down automatically at stoplights to save fuel.

Ferrari's performance strategy is to add 1 additional horsepower for every kilogram of mass added to its hybrid cars. In fact, its recently unveiled hybrid concept car actually accelerates more quickly than the standard 599 GTB Fiorano model. Critically, that extra weight must be distributed in a way that doesn't spoil a car's handling balance or intrude unduly on passenger and cargo space. Virtually every sports-car maker is designing batteries and hybrid components to fit into a thin "skateboard" entirely under the car's floor, lowering the vehicle's center of gravity.

The Tesla Roadster, which is based on the gasoline-powered Lotus Elise, proved that EVs can be fast and fun. But they still don't outperform comparable gasoline models, especially in handling. That goes for hybrids, too. Much has been made of an electric motor's ability to deliver its full monty of torque the instant you mash the gas-er, throttle. But for pure EVs, those motors must counteract hundreds of kilograms in batteries, cooling systems, and electronic controls. Take the Elise, a featherweight at less than 910 kilograms (2000 pounds). It gains more than 300 kg (660 pounds) of electric fat in its transformation to the electric Tesla Roadster. And because batteries run out of energy so quickly, especially at higher speeds-a single gallon of gasoline contains 33 kWh of energy, about two-thirds of the energy stored in the entire battery pack of a typical EV-electric cars are generally limited to 200 km/h (125 mph) or less; your mom's Toyota Camry can go faster.

Fortunately, electric motors themselves are much more efficient than internal combustion engines, losing much less power between the motor and pavement. That's why an electric vehicle can travel 25 or more kilometers on the energy equivalent-from its batteries-of barely a liter of gas. Of course, those batteries are heavy and can't store nearly as much energy per cubic centimeter as gasoline does. "If you're carrying enough battery for a 200-mile range, a lot of the time you're dragging that battery as deadweight and actually hurting your handling and fuel economy," says Peachey, the Lotus engineer. So in real life, your choice comes down to limited range or a hybrid drivetrain. Lotus, Porsche, and Ferrari are all going the hybrid route. They can travel, say, 55 km (about 34 miles), on electricity alone. A supplementary engine eliminates the "range anxiety" of a pure EV, allowing smaller, lighter batteries and a less-powerful electric motor.
But electrics hold intriguing advantages as well. Multiple electric motors allow "torque vectoring"-independent control of the drive speed of each individual wheel to improve cornering, stability, and safety-with no need of complex mechanical or hydraulic differentials to divvy the power among the wheels (BMW and other manufacturers are already applying torque vectoring to their gasoline-powered all-wheel-drive cars).

Next up will be electric wheel-hub motors, which will push the performance envelope even farther. Michelin, for example, has been developing its Active Wheel system for over a decade. It puts a motor, a brake, and suspension control in each of a car's four wheels, eliminating the need for an engine, traditional suspension, gearbox, and transmission. This offers formidable performance: A typical sports car takes roughly 6 seconds to stop from 100 km/h; Michelin's concept system can do it in 2.8 seconds.
Gearheads may worry that today's speed merchants will be shackled by environmental demands, just as the original '60s muscle cars were driven to extinction by the first-ever emissions rules. Yet a modern sports car like the Corvette Z06 somehow manages to combine an impressive 26 mpg with 505 hp and a 198-mph top speed, figures that shame any car of the '60s. (For those of you in the metric realm, that translates as 9 L/100 km, 377 kW, and 319 km/h.)

An optimist might gather that there's nothing to fear: Ferraris and Corvettes will still be duking it out, going faster and handling better than ever. This time, though, the drivers will have a new metric to brag about: fuel efficiency.

GE Wattstation: http://www.geindustrial.com/products/static/WattStation/

By Ellen Kathrine Hansen, IEEE Spectrum, August 2010

Judging by looks alone, you'd never guess that the simple one-and-a-half-story house on a residential street outside Århus, Denmark, is anything more than an ordinary single-family home. The stylish little house has the broad windows and long sloping roof of a typical Scandinavian home; a trampoline sits on the neatly trimmed lawn.

But this house is different. Using ecologically benign materials, a rooftop of solar panels, and energy-scrimping designs, the house generates more than enough power to run itself.
Inside, a family of five is testing out the ultimate model home. Windows in all four walls and a slanted skylight flood the first floor with sunshine. Built-in blinds twitch autonomously to adjust to the glare, angling their slats just so. To bring in more fresh air, the skylight slides open with a hiss. "It's fun to listen to," the children report.

The family is now nearing the end of its 14-month sojourn in the Home for Life, the first prototype of a Danish concept known as an "Active House." At this point they no longer really notice the house's impressive array of technologies or its subtle machinations as it works to secure their comfort. Specialized windows, tight insulation, and a climate-control system minimize the need for electricity and heating. The sun handles the rest: Solar panels, solar thermal collectors, and the Home for Life's south-facing orientation allow the house to generate enough electricity and heat to make it carbon neutral. What's more, the use of building materials that can be produced with less energy means that the emissions from their manufacturing will be canceled out in about 40 years.

Granted, it's a little funny to be watched and studied this way-even by a professional anthropologist," wrote Sophie and Sverre Simonsen in their online diary last September. The Simonsens had lived in the house for 3 months, and it was already abundantly clear that this was going to be an unusual year.
An anthropologist had asked the young parents to map their movements through the house. We'd designed the core of the house as a "light cross," which cuts through the 40 square meters that make up the kitchen and dining area and the living room, and we wanted to know if this design worked for the family. To minimize the need for artificial lighting, we designed the space so that daylight pours in from all four points of the cross, which also serve as exits, ventilation openings, seating recesses, and frames around a view. The family's records showed that they were indeed content to spend the bulk of their time in the light cross.

We needed the Simonsens' reflections because the raw data tell an incomplete story. Just looking at the numbers, the summer months were spectacular: The house generated 800 kilowatt-hours of electricity last August, used just a bit more than half of it, and fed the rest back to the grid. But did the family actually enjoy living here? We were curious whether they were sick less often or missed fewer days of work-or not. Our test family has helped us decipher where we've succeeded and where we still have work to do.

The rationale for this holistic approach to architecture is straightforward. Many modern buildings are toxic, and they consume way too much energy. We estimate that about a third of buildings today have an unhealthy indoor climate, which can exacerbate allergies and asthma, affect a person's ability to concentrate, and even trigger depression. The built environment is also a significant energy burden-around 40 percent of an industrialized country's energy goes to its buildings. That's not surprising when you consider that we spend around 90 percent of our time indoors. But it doesn't have to be that way. One of the goals of VKR Holding, which has invested in several companies dedicated to improving the internal environments of homes, is to start turning some of those numbers around.

There are a few ways to do this. One approach is to design houses with small windows and thick walls filled with insulation; this strategy prevents the sun from overheating the interior, cuts down on air-conditioning in the summer, and reduces heat loss in the winter. But it doesn't make for a delightful living experience. The people living in one such house complained to me that it was so heavily insulated you couldn't even hear birds singing outside.

So we decided to build a house that didn't wall itself off like a fortress from the sun but instead invited sunlight and fresh air in. In a word, that means windows. Our test house has about double the window area of an ordinary Danish house. We chose specialized panes with two or three layers of glazing, which in the cooler months reduces the heat escaping from the inside while allowing lots of heat and daylight to enter. In fact, the windows alone deliver half of the heating needed in the winter.

The windows' frames also add insulation. They're made of a brand-new type of polyurethane (the stuff that foam is made of) strengthened with thin glass threads. Engineers at Velfac, a VKR subsidiary, tested more than 200 materials before finding one that was at once highly insulating and durable and had a pleasing surface finish. Because of the material's strength, a weather-resistant frame can be made with just a slim sheet of this polyurethane.

The large windows cut down on the amount of indoor lighting and mechanical ventilation needed-good news for our net-zero-energy goal. But sometimes we need to keep the interior heating in check. To do so, a roof overhang on the south side provides shade when the sun is high in the summer, and shutters and blinds on both sides of each window regulate the transmittance of heat and provide privacy.

To further reduce the risk of overheating, we programmed the windows to open on their own to let in fresh air. Sensors in every room track the temperature, carbon dioxide levels, and humidity, and a weather station on the roof monitors outside conditions. Our control system, from another VKR company, WindowMaster, uses that information to decide when to lower the solar screens or slide open selected panes. These automated adjustments of the windows, rather than traditional air-conditioning and heating, provide the bulk of the house's temperature control.

Unfortunately, the settings we chose didn't always agree with the Simonsens. As the parents reported, "The windows are open even though we feel cold. There is a draft, so we wrap ourselves in blankets and close the windows with the remote control...but alas, half an hour later they open automatically again!"

It took several months for the family to adjust to their Active House. On first entering, a casual observer might be taken aback by the house's autonomy. The sound of the shutters adjusting or a window sliding open can make the house seem eerily sentient. One of the challenges we faced was balancing the need for precise control to keep the energy demand low with the desire to hide the engineering from the inhabitants.
Sophie jotted down her reactions as the family slowly became comfortable with its animated home. Some of the house's peculiar habits persisted, though; the lights, for instance, would switch off unexpectedly, even when a room was occupied. "I rocked back and forth in the chair to ensure that the light did not go off," she wrote. "It gives a whole new meaning to 'Active House,' but from outside it probably looked pretty crazy."
So how do you power a self-governing house?

In total, the Home for Life ought to use about 60 percent of the energy of a traditional single-family house in Denmark: 15 kWh per square meter per year for lighting, household appliances, and running the active components of the house and 32 kWh/m² per year for hot water and heating. It's the latter where the Home for Life really stands out: Its heating consumption is just half that of an ordinary Danish home. Once all the systems are fine-tuned, we estimate that the house will generate a surplus of about 9 kWh/m² per year.
The shape of the house made a big difference. Its overall surface area was kept to a minimum because that is a major factor in heat loss. In addition, the tip of the roof is tilted to the north, which increases its surface facing south. That side of the roof is covered with solar panels, solar thermal collectors, and skylights, each of which plays an important part in determining the house's overall energy budget.

First, let's look at the electricity. The 50 m² of polycrystalline solar panels generate about 5500 kWh a year. That's 20 percent more electricity than the house needs, although in winter it does draw some power from the electricity grid. These solar cells, with 13 percent efficiency, aren't the best on the market, but they're a good compromise for the price.

Then there's the heating, which comes in through the windows or the solar thermal collectors. The 6.7 m² of collectors catch the sun's rays on copper plates installed on the lowest part of the roof. Underneath the plates, copper pipes circulate a fluid that absorbs the heat of the plates, converting 95 percent of the sun's energy into heat. The collectors can catch indirect sunlight, too, so the house still has heat on cloudy days.
Should more interior heating be needed, we use an air-source heat pump. In one common configuration of this type of pump, air passes through a heat exchanger placed outside the house to transfer the air's warmth to a liquid. The liquid travels to an electrically powered compressor inside the house, which applies pressure to raise the fluid's temperature further. In general, a heat pump is far more energy efficient than conventional oil or electric heating, and it has lower CO2 emissions, too. But the pump's performance depends heavily on the amount of heat contained in the air; when it's cold outside, these heat pumps aren't efficient.

To avoid that problem, we used a heat pump designed by another VKR subsidiary, Sonnenkraft, which uses the solar collectors to preheat the cold winter air before it reaches the heat pump. The pump can now easily produce 20 °C water even when the outside air is below freezing. After the liquid is compressed, the heat travels through pipes in the floors and to radiators. In all, our solar collectors and pump can produce about 8000 kWh's worth of heat a year.

Generating power and heat was only part of our design goal, though. Equally important to us was the wish to pay off the energy invested in the materials. To meet that challenge, we chose materials that require less energy to produce. We used wood for most of the construction, with a few steel beams added for load-bearing parts of the structure. We made the facades and roof out of natural slate rather than brick, which has a larger energy footprint.

Our careful innovations and calculations didn't always line up with the family's preferences, however. As the weather grew colder, the Simonsens complained that they weren't warm enough. We ended up raising the temperature of the heating under the floors by 2 degrees, and we stopped lowering the room temperatures at night.

The net result was, of course, an increased energy load. Fortunately, we'd overestimated how much electricity the Simonsens would use for lighting and appliances, so we reduced our estimates for those activities from 3.5 watts per square meter to 2 W/m². Then again, they sometimes kept the blinds drawn during the day-for privacy and to reduce glare-which lowered the amount of radiation available to heat the house.

In time, though, we think the Simonsens would have kept the blinds open more as they grew to understand how the windows affected their energy consumption. We know the family recognized the house's energy performance and is proud of it. On one particularly bright day, Sverre examined the computer display in the hallway that charts the house's energy performance, and the power of the sun truly hit home. "It was obvious here on Sunday when the sun came out," he wrote in the family's diary. "I just had to go and check: Was it really affecting energy output? Yes it was! That was a real 'ta-da!' moment."

We plan to share all these observations and data with the world in a new set of metrics we're now drafting, which encompass not only theoretical energy consumption but also the environmental impact and the inhabitants' well-being. We've also begun the next three Active House experiments: Green Lighthouse, a round building on the University of Copenhagen campus, as well as two single-family homes in Austria and Germany.

The Simonsens will be moving out of the house in one month, and the Home for Life will go on the market. If the family's satisfaction is any indication, we're well on our way to proving that environmentally friendly, carbon-neutral homes make for happy, satisfied inhabitants.
This article originally appeared in print as "Home, Smart Home."

About the Author
Ellen Kathrine Hansen led the design team for a futuristic green house in Århus, Denmark, named Home for Life. She drew inspiration from her childhood, which she spent in an even greener place-Lolland, a Danish island known for its sugar beet fields. She left Lolland to attend architecture school at the Royal Danish Academy of Fine Arts, in Copenhagen, where she now lives. Hansen says that when she took her 5-year-old daughter to see the Home for Life, she asked, "Mom, why don't we just live here?"

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