Solar system

Architectural Review, The, July, 1994 by Amanda Greenhalgh

This factory, half-way between San Francisco and Sacramento, uses photovoltaic technology applicable to buildings in hotter, less clouded climates and makes a small but important step towards more environmentally sensitive architecture. Well, we've all thought about it before. After the space probes, after the amazing advances in silicon-based technology of the past three decades, we have been wondering how solar energy could be used directly to make electricity to run buildings. How a building's epidermis could be, instead of a big problem for energy management, a net contributor to control of internal climate.

The Advanced Photovoltaic Systems Manufacturing Facility at Fairfield in California has been set up to make photovoltaic panels by mass production for large-scale applications that range from consumer uses to huge solar power plants. The panels it produces are the largest (2ft 6in by 5ft) manufactured in the USA. They consist of a glass substrate coated with tin oxide (a transparent electrode) which is covered with three layers of silicon and then a coat of aluminium film (the other electrode). The firm aims to make 2.5 million sq ft (230000[m.sup.2]) of panels a year, mainly for use in the building industry.

From the outside, unless you know the script, the building is not particularly remakable. From the distributor road that runs along the south side of the long east-west oriented rectangle, a grey wall of lift-slab concrete punctuated irregularly by glass blocks establishes that this is a semi-automated factory, more crisply detailed than most, but not particularly memorable. A long and elegant curved metal canopy indicates the parts of the building most used by people (as opposed to the big shed which is mainly the domain of machines). A glass-clad cube projects from the concrete's hard line against the sky. It signals entrance, with the reception area and cafeteria on the ground floor, and a visitors' centre and control room above.

These lightweight additions to the building's massive concrete bulk are the only areas in which the firm's product is used extensively. Panels above the canopy and in the upper part of the cube (and its roof) provide enough power to light and air condition the control room and visitors' area.

The architects have carried out studies, funded by the US National Renewable Energy Laboratory in Golden, California, to assess the economic viability of using photovoltaic panels in building. Their conclusion was that the cheapest method (in terms of rapid return) was to use panels as part of a conventional curtain wall, rather than devising angled panels (which offer 35 to 60 per cent more energy), for which the detailing of supports would cost more than can often be justified.

But in hotter and more cloudless climates, in building types ranging from offices to homes where angled sun protection is normal to allow users a view of the outside while protecting the interior from excessive insolation, surely combinations of shading devices and photovoltaic panels (perhaps the new semi-transparent kind) could lead to new architectural expressions -- and much more energy-efficient buildings.

The Fairfield plant is a cautious start. But if the product takes off it may be possible to use the possibilities of photovoltaic panels more extensively. The factory is funded by a partnership of the City of Fairfield, private capital and the sheet metal workers' union's national pension fund. One of the aims of the last is to provide new opportunities for the skills of working union members. The union has shown a kind of vision that has vanished from western capitalism since the New Deal; it is an example to those pension funds that are only too ready to invest in organisations devoted to destroying jobs to maximise quick returns.

The building is in many ways ordinary. But, as is proper in a building partly funded by labour, the common areas are pleasant and even jolly, with colour and materials used to telling effect within a very tight budget. Plain as it may be, the Fairfield plant is a pointer of hope to a more civilised future.

[CHART OMITTED]