SOLAR panels that generate electricity are bulky and expensive. But now an
American company says it can provide unobtrusive photovoltaic panels at
half the
cost of traditional versions.

The new technology will be on show at this month’s Olympic Games in Atlanta,
Georgia, where the US Department of Energy is building a solar-powered
house. On
the roof are 110 solar shingles supplied by Energy Conversion Devices (ECD) of
Detroit, Michigan. “From the ground, it’s hard to tell the difference between
the asphalt shingles and the solar ones,” says company chairman Robert
Stempel.

Traditional photovoltaic cells are built by growing silicon crystals,
slicing
them into wafers 100 micrometres thick, and encasing them in glass. This
process
is now about as cheap as it is going to get, and assuming a cell lifetime of
around twenty years, the electricity from crystalline cells is still
roughly two
or three times as expensive as electricity from fossil fuels. The cells of
solar
shingles, on the other hand, use noncrystalline silicon and are one hundred
times thinner. Mass production will probably reduce the cost to half that of
conventional cells. They should also be cheap and easy to install. Roofers nail
the shingles to the roof base as usual, and electricians wire them
together from
inside the house.

ECD’s manufacturing arm, United Solar Systems Corporation, begins with
a roll
of stainless steel sheet 800 metres long and 35 centimetres wide. The steel is
fed through a series of rolling machines, “much like newspaper production”,
according to company vice-president and electronics engineer Subhendu Guha. The
machines deposit nine layers of amorphous silicon on the steel, followed by a
protective layer of transparent polymer. Finally, a coloured top coating
ensures
that the shingle blends in with surrounding roof tiles. The shingles work
in the
same way as conventional cells. Photons knock electrons from the valence band
into an energy level called the conduction band, where they form an electric
current.

According to Guha, 400 square metres of photovoltaic
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of an average suburban American roof—exposed to six hours of sunlight per
day can power the average home. At the moment, the company’s thin-layer
technology is not as efficient as the crystalline silicon cells at converting
sunlight. Some traditional cells achieve up to 17 per cent conversion,
while the
new cells reach a little over 10 per cent. But the efficiency of the new
devices
is improving all the time.

A combination of higher utility costs and government subsidies means that
Japanese and German householders are likely to be the first major customers.
From next year, thousands of Japanese residents will be eligible for a
government subsidy that pays for half the cost of installing the photovoltaic
system of their choice. Germany is considering a similar programme. Japan plans
to eliminate the subsidy gradually as economies of scale help solar energy to
compete with fossil fuels. ECD already has a foot in the door of the Japanese
market through a partnership with Canon.

“I find the concept very interesting,” says Ajeet Rohatgi, a photovoltaic
expert at the Georgia Institute of Technology in Atlanta. “The next step to
bring costs down is to have photovoltaic panels replace the whole roof.”

The intention behind the procedures remains the same: to remove dead tissue and reshape what lung remains so that it can function more normally. “I don’t want to send out any messages of false hope, but no one’s calling this experimental any longer,” says Alex Little, a thoracic surgeon at the University of Nevada. “We’re looking for long-term results.”

People who develop emphysema eventually find each breath a struggle. As the disease dismantles lung tissue, it leaves behind scarred sacs of air called bullae. The body struggles on with what tissue remains, but the bullae take up more and more room inside the patient’s chest. “The lungs get so overinflated that you can’t take a breath,” explains John Eugene, a thoracic and cardiovascular surgeon in Los Angeles, California. “And when you do, you can’t get it out.”

Eugene customises his approach to each case. First he combines data from X-rays, CT scans and other imaging methods with breathing tests to characterise the type and extent of damage. Large pockets of bullae generally mean opening the chest, cutting out the dead tissue, and perhaps stapling the edges of healthy lung back together. “But if the emphysema is diffuse, bullae are mixed in with healthy tissue, and we may use the laser,” he says. “If we can combine it with thoroscopy, that’s the least invasive and patients are getting up the next day.”

In this procedure, called lung-reduction pneumenoplasty or LRP, the surgeon makes three small openings in the patient’s chest and inserts a miniature videocamera and a low-energy laser. He manoeuvres the instruments to the diseased regions of the lungs, where a television monitor pictures bullae as grey, membranous “blisters” of air. Then the surgeon turns on the laser to burn them away.

“The theory has always been that functioning lung is not affected by radiation because it has normal blood flow, which cools it off and prevents damage,” says Eugene, who has used the new technique in about 40 operations since early 1994. “Diseased lung, which has lost blood vessels, will respond by contracting and plicating, somewhat like a pleated skirt. It’s a thermal reaction.”

LRP reduces the lung by about 25 per cent, which eases the overstretched chest wall and allows the diaphragm to return to its normal position.

“More than 85 per cent of these patients can breathe better, can exercise lightly, and say that they would go through the operation again,” says Little. “Instead of the 25 per cent who die within the first year [of reaching this stage], we’re seeing 90 per cent survival in the year after surgery.”

People with advanced emphysema, most of whom are elderly, usually have only a 20 per cent chance of surviving five years, according to Eugene. His earliest patients are still breathing better by the time they reach the two-year mark.

The circus’s Clown Care Unit has been sending clowns into six New York hospitals for three days a week for nearly 10 years. And because staff and parents seem convinced that the laughter these performers bring to the wards does help sick and anxious children, the researchers are trying to determine scientifically whether their brand of therapy really works.

Starting this month, the children of the Babies and Children’s Hospital of New York at the Columbia-Presbyterian Medical Center will be the focus of three studies designed to analyse the effects of humour on a cross section of patients undergoing a range of treatments.

“We’ve had plenty of anecdotal evidence that our clowns are helping sick kids heal,” says Jane Englebardt, who oversees health and community programmes for the circus. “Kids, parents, the medical staff – they all say ‘hey, this is really something’. Now we’re going to see whether that ‘something’ translates into shorter stays, less medication, just in general better quality of care.”

The researchers, who are experts in fields ranging from child psychology to paediatric anaesthesia, all at Columbia University’s College of Physicians and Surgeons, want their laughter to be spontaneous. So they are keeping the details of their studies – and even their identities – secret so that neither the clowns nor the patients know they are being studied and feel self-conscious. If the cover was blown, notes one of the researchers, the study’s scientific credibility would be lost.

They have revealed, however, that in future the clowns will go where no clown has gone before. “I like to say that we’ve always had clowns in the operating room,” says one of the researchers. “Now we’re going to have professional ones.”

With such “procedures” as kitty CAT scans, chocolate-milk transfusions, and red-nose transplants, the clowns have helped to alleviate children’s anxieties before and after they undergo the real thing.

“We’ll look at whether children cope better with invasive or medical procedures when they’re getting distracted, cheered up,” says another of the team. The clowns will now work their magic during “scary, painful things”, he says, for example, when a nurse inserts an intravenous drip or an anaesthetist puts them to sleep for an operation.

Todd Robbins, “Doctor T. L.”, has been a white-coated CCU clown for nine years. “We’ve quickly discovered that our presence alone seems to lighten the atmosphere not just for the kids, but also their parents, relatives, and yes, doctors, nurses, and staff as well.”

Robbins entertains children who are about to undergo bone-marrow transplants, physiotherapy, treatment for AIDS and cancer, and emergency care.

The studies, overseen by Columbia’s Rosenthal Center for Alternative/Complementary Medicine, will evaluate the success of the clowns’ particular brand of therapy with a rating scale based on crying, difficulty keeping still, expressions of pain, and other factors.

“Nobody likes to see a child suffering,” says one of the team. “We hope to improve the atmosphere for everyone.”