The Passive Solar Dome Greenhouse

The term "global warming" was first used in 1975, two years after the first oil shock slugged the U.S. economy. Four years later, a second shock coincided with the Iranian Revolution. That same year, John Fontanetta and Al Heller published The Passive Solar Dome Greenhouse Book A thrift-store edition, bright green and yellow, fell into my hands a few years ago. It was the result of a research project at Fordham University called FUSES: Fordham Urban EcoSystem. The project seemed to stir up some real excitement -- my first edition copy has a quote from Buckminster himself on the back, bolstered by New York Magazine and CBS. 

At times dismissed as kitsch, or embarrassing in its earnestness, I've long had an affinity for seventies design. Ken Isaacs, Buckminster Fuller, Steve Baer, Paolo Soleri, Lloyd Kahn, Jersey Devil, The Prickly Mountain boys -- instead of just fiddling with the formal aspects, they tackled architecture in all its complexities, approaching it with craftsman's sensibility and a DIY spirit. They questioned assumptions about community, social justice, building techniques, and environmental responsibility. The results were wildly uneven. It was kinetic. It was weird. It didn't cost much, and a lot of it didn't last. Today, warped by digital speed, economic instability, and climate change, strains of that old anarchic spirit are punching through again. 

 Graphic design back then seems so warm.

Graphic design back then seems so warm.

The Passive Solar Dome Greenhouse Book (PSDGB) is a perfect artifact of that era. The tone --  an optimistic, casual certainty -- reminds of much of today's techno-libertarian hopes for self-driving cars and sustainable food sludge. Each chapter runs neatly along a timeline of construction, from solar siting to site selection to woodworking. The final product is an ingenious home-cooked 23' dome, built from 2"x2" struts and plywood plate hubs. It is covered in two layers of transparent plastic with taped seams. Insulation shields the northern side, and black-painted oil drums (a nice conceptual callback) filled with water provide thermal mass. Growing is done right in the soil, isolated from the surrounding earth with a vapor barrier-lined trench. 

The basic stats are very promising: $600 ($1,900 today) in materials, 415 S.F. of growing space, and 50-degree soil through a New York winter. FUSES successfully experimented with a wide range of vegetables and a 750-gallon tank full of tilapia, the seventies' researcher protein of choice because it thrived on a vegetarian diet in close quarters. At least one of the collaborators on the project, Barbara Devey, spent two years setting these greenhouses up as community gardens on vacant lots across New York. The intention was to pilot low-cost, sustainable, year-round food production, especially in urban areas. Other folks were tackling the same problem around that time: how to make closed-loop artificial ecosystems that could hyper-localize food?

 The diagrams throughout are beautiful, clean, and clear.

The diagrams throughout are beautiful, clean, and clear.

The New Alchemy Institute, founded in 1969, was a research center interested in questions of radical politics as much as food production and architecture. They built a series of greenhouses in Cape Cod and Canada that they dubbed "bioshelters" -- self sustaining systems, under glass and functional with only water and sunlight as inputs. Process was meticulously documented in a series of quarterly journals. The Institute disbanded in 1991, but the concept is has gained new currency with the advent of rooftop farms in Brooklyn and post-industrial vertical farming in Chicago

Around that same time, Paolo Soleri was first building greenhouses at Arcosanti. Ultimately, he planned to fuel the whole city with an energy apron that draped over the edge of the mesa and pumped hot water and humid air into the living units. The first prototype units, built down in camp, were simple shed-shorn rectangles, topped with a stretched plastic membrane. Inside, C-shaped concrete sections cradled container-ized plants and reflected solar energy onto the plants. A clever system that used a pivot point in the floor and a circular "umbrella" of pipe was used to tension the plastic and prevent wind action from shredding the roof. 

In middle school, for a class project, I stumbled across James DeKorne's Survival Greenhouse at the library. He advocated a sunken pit design to minimize heat loss, raising tilapia in tanks and using the dirty fish water to feed hydroponic beds. Underneath the raised planting troughs, he kept chicken and rabbits, whose emissions artificially raised the carbon dioxide levels in the air and supercharged both photosynthesis and temperatures. 

 Arcosanti test greenhouses, via Flickr user  A. Thompson . Note faint white ring in lower right; that is the internal tensioner pushing the plastic out in the middle to keep it taut.

Arcosanti test greenhouses, via Flickr user A. Thompson. Note faint white ring in lower right; that is the internal tensioner pushing the plastic out in the middle to keep it taut.

The New Alchemy, Arcosanti, and pit designs all did one notable thing: they rejected the dome shape. The advantage of mirroring the shape of the earth and conveniently tracking the sun is offset by the fact domes are hard to build. FUSES did an admirable job of breaking the geometry down into a low-waste, simple-to-assemble process, but building a circular building out of rectangular materials is a challenge. It is a hard shape to sheathe, make watertight, and repair. Geodesic designs require high-strength materials to function properly as balanced structural equations. Lloyd Kahn, once a high priest of the form, eventually defected from the church of Bucky due to practical concerns. Other experimenters who worked on the problem for a longer time period generally settled on sloped-roof shapes that gave up some solar potential for ease of construction and maintenance. 

I've always wanted a greenhouse like one of these. It seems like a way to urbanize the homesteading dream, packing in backyard chickens and a quarter-acre goat with year-round fresh vegetables. I'd be canning and pickling and home-brewing beer and gutting fish after work for a greenhouse-to-table supper on a random Tuesday night. The supermarket would wither in my absence. But actually wrenching a whole diet from one of these would be a hard, full-time job. The compression and high yields don't eliminate the work -- they just make it mildly more convenient. 

The concept of closed-loop greenhouses still as sound as it was 35 years ago, and the technology to execute it properly has only improved. Winter produce doesn't have to be shipped in from Florida, or for that matter, Mexico. Colorado seems to have figured this out; hopefully the rest of the country will follow, Victory gardens for a new age and a new battle.