Caring for Heat: Re-presenting Geothermal Energy at the Eden Project
This past June, Eden Project began pumping heat from a new geothermal well into its iconic domes. Located in Cornwall, England, Eden is the well-known, well-attended, self-described “living theatre of plants and people.” Its twenty acres of outdoor gardens are populated with two thousand varieties of plants; its greenhouses, designed by Grimshaw Partners and opened in 2001, house Mediterranean and rainforest biomes. In short, it is a thriving biologically oriented eco-tourist destination. Why, two decades after opening, did it introduce this deep earth energy system? More curiously, why did it not integrate, spatially and aesthetically, the Eden Geothermal facility — which arguably has as much to teach the public as Eden itself — with the gardens and greenhouses just a kilometer away?
Figure 1: Google Street view of Eden Geothermal plant. Although visible from the entrance to the facility, the 55m tall rig is hard to find from just a few yards away. The rest of the facility, including the pumping units, lagoon, and heat exchanger is hidden through distance and plantings.
The answer to the first question is straightforward. Eden needs the heat to keep exotic flora in its indoor biomes alive. And, ideologically, it needs that heat to come from a local and sustainable source, a source whose relatively low environmental impact is consistent with the project’s Earth-friendly ethos. Relying on geology for energy also recalls the project’s past — while announcing its future. The park is located in a disused “China clay” pit mine that opened in the nineteenth century. And if things go according to the original plan, a second well will be drilled, this time to supply cheap and clean heat and electricity to well beyond the park, to the surrounding region.
This brings us to the second question. Given the historical connections, the aspirations for the future, and Eden’s mission — which includes being a model for a new relationship between humans and non-humans in which nature is better admired and cared for — why obscure the system? It would seem, to the contrary, that the Eden Geothermal plant would be of great value, and interest, to park visitors, both in Cornwall and at the several other locations around the world where Eden has plans to open versions of itself. Despite the obvious paradox of artificially recreating versions of far-off environments within highly engineered greenhouses (and the long colonial and capitalist history of such endeavors), Eden’s sponsors see it as an educational tool encouraging people to reconnect and fall in love with nature. Geothermal energy, with its intentionally spectacular combination of naturally occurring and highly engineered objects and processes, is nothing if not consistent with these goals.
Yet, despite its clean energy attributes and close proximity to the park, there are no plans to make the well part of the visitor’s eco-experience. And like much contemporary infrastructure, it has not been designed with an aesthetic or educational agenda. Instead of taking the opportunity to turn it into another icon to educate the public about geothermal and to engage the site’s, and the culture’s, fraught relationship with the latent energy that lies beneath the Earth’s surface, it is at best invisible, or, at worst, an indifferent if not ugly machine in an otherwise immaculate garden.
Figure 2. Alexander von Humboldt, Diagram of a Cross-Section of the Earth's Crust, 1841. From Heinrich Berghaus, Physikalischer Atlas (Gotha: J. Perthes, 1852). The preeminent scientist of the 19th century, von Humboldt created or commissioned a series of large cross section drawings that emphasized the relationship between geological and biological developments, illustrating his understanding of the Earth as a singular, interdependent system.
Geothermal systems like the one at Eden are made possible by the fact that the deeper one goes underground, the hotter the Earth. Much hotter. While there are local variations determined by tectonic conditions, the rule of thumb is that for the first 100km below the Earth’s surface, the temperature increases at an average rate of 30°c per kilometer. At the Cornwall site, this means temperatures of 170°c to 190°c 4.5km below ground. Harvesting this heat, however, requires a specific geological condition. A loop must be created between two pipes, one that sends cold water down, one that brings boiling water or steam back up. But the system can only be set up in zones of subterranean rock that have naturally occurring gaps. Relatively few places in England are suitable. Cornwall is an exception.
At Eden, the first section of the supply (cold water) pipe travels straight down for 1.7km before it is angled to meet this stratum of porous rock. At the bottom, the boring is only 25cm wide. The water that comes out fills the gaps in the rock and absorbs its heat. The highly pressurized water or steam is then returned to the surface through the second pipe. Once above ground, the energy in the water can be used directly as a heating source or to produce electricity. The water itself returns to an on-site reservoir, where it is cleaned and reused. It is an almost perfectly closed system, with very little loss of material or energy.
All these operations occur in a relatively small site adjacent to Eden’s public spaces. The thin, deep boreholes are topped by a relatively tall (55m) tower of strictly utilitarian design that stands out from its surroundings and could be mistaken for a cell tower or oil rig. The rest of the industrial looking facility is hidden by trees and shrubs planted on the edge of the road leading to the park. And while the drilling rig is prominent, it is humble in comparison to the monumentality of Eden’s domes and picturesque grounds. Still, its presence is felt as it points to the sky that it hopes to keep clean, while also indicating, like other energy infrastructure, its deep connection to the ground below it.
Perhaps Eden is hiding the geothermal plant because to showcase it would draw attention to the fact that the well-being of the life supported at the gardens and greenhouses is artificially maintained. Or perhaps it is because energy infrastructure is typically understood as unattractive, and thus unworthy of aesthetic attention. Aestheticizing nature is one thing; doing the same for infrastructure, by contrast, seems wasteful. Why care what a machine looks like as long as it works?
Yet, given how the performance and the beauty of flowers, grasses, trees, birds, and architecture at Eden are celebrated, and the meticulous design of the landscapes and buildings on the property, could not the function and beauty of the geology, the heat it will supply, and the structures that support it, also be celebrated? Not least in order for them to be better understood and cared for. Or, if not celebrated, at least put on display? What is the function of keeping such things invisible?
“Why exaggerate the architecture and gardens but allow Eden Geothermal to be concealed?”
For all the effort to turn a “derelict” mine into a beautiful “world of life,” it would seem that the heat being extracted out of the Earth at Eden Project deserves, if not demands, aesthetic attention. If Eden, as it claims, is truly a facility that is “underpinned by the understanding that we need to live with the grain of nature and that everything is interconnected, “surely it should also engage and represent the inorganic matter on which life depends. As French sociologist Bruno Latour argued, it’s critical, after all, for humans to be mindful of all such relationships in the Earth’s “critical zone.” How else will visitors, and the broader public, know to understand, respect, and value Earth’s heat as much as they do the flora of the Mediterranean housed under Eden’s steel and plastic domes?
One reason for inattention to the well may be that unlike plants, the heat in the ground is invisible. It is also dangerous. It needs to be manipulated and isolated to become useful. But this dynamic underscores why representation is so important, especially at Eden. How should one draw attention to this necessary danger in a place where nature is presented as a bucolic spectacle? Representing the geothermal process and its relationship to Eden would not only require different techniques, forms, and sensibilities, but a different mindset about the Earth and about infrastructure.
The uncanny and the sublime, as I and others have written elsewhere, are two artistic modes that have long been used to express powerful natural forces. Another are cosmograms. Cosmograms are aesthetic objects or images that symbolically depict the multiple interrelationships and timelines found in the geological, biological, and atmospheric realms. Historian of science John Tresch describes them as “material assemblies using words, images, numbers, songs, stories, or monuments to convey the order of the universe as a whole.” Mandalas and temples are two religious examples. Skyscrapers and space ports are more modern ones.[1]
Figure 3. Hildegaard von Bingen, Cycle of the Seasons. From Liber Divinorum Operum Lucca, c.1150. Von Bingen was a polymath, adept in science, art, music, and religion. Her depiction of the four seasons includes a variety of human and non-human figures that illustrate the relationship between earthly, celestial and mythical agents, an image of diverse yet complete universe.
Although a sectional drawing through Eden and Eden Geothermal could function as a cosmogram,[2] the site itself already acts as one. It creates, and depicts, an intimate relationship between the heavens and the earth. It actively integrates the soil with the sky and the sun. It puts on display how the small and speedy flora and fauna are connected to the much larger, longer, and slower lives of celestial bodies, including the body of the Earth. Eden’s combination of natural and industrial materials and processes represents the multiple durations found in the site’s natural and human histories.
Yet while these relationships are present, they aren’t always recognizable. This is one reason why Eden Geothermal should have more of a visible presence. Why exaggerate the architecture, the atmosphere, and the surfaces of the gardens but allow the infrastructure and landscape of Eden Geothermal to be concealed? Do we depend less on, or care less for, the energy under the earth’s surface than the life above? Certainly, we depend on it. Certainly, we could care more for it.
Making its geothermal plant more prominent would render Eden’s cosmogram legible. Doing so would allow visitors to recognize the (literally) deep relationship between life and energy that sustains the world as we know it. It would also underscore the importance of the aesthetic in generating public interest in environmental work. Here aesthetics is not defined as an added element conceived to make something attractive or to distract one from more pressing matters. Instead, it is closer to its original meaning: a means for producing knowledge of the word via the senses. Aesthetic artifacts can bring to our senses, and then to our minds, what is everywhere present but often unexpressed. Sometimes you can’t know, let alone change something until you are made to see it, touch it, or smell it.
Citation
David Salomon, “Caring for Heat: Re-presenting Geothermal Energy at the Eden Project,” PLATFORM, Oct. 2, 2023
Notes
[1] David Salomon, “Modern Mundi,” New Geographies 11: Extraterrestrial (2020), 43-48.
[2] David Salomon, “A Theory of Architecture Through the Geologic-Atmospheric Axis, or, Sections as Axis Mundi and Cosmograms,” in Pedagogical Experiments in Architecture for a Changing Climate, ed. by Tulay Atak et al., forthcoming in 2024 (New York: Routledge, in press).
