51 Million BTU’s/ Metabolism Study/C₃H₈, e^-, NaCl, is a video installation engaged with the transformation of energy expended in a group of site-process works of the late 1980’s. Using the projection of video on a rock-salt-surfaced screen, 51 Million BTU’s/ Metabolism Study/C₃H₈, e^-, NaCl, visually and metaphorically expatiates upon scientific ideas initiated in the site projects about the ancient solar origin of fossil fuels. These concepts briefly state that Mesozoic-Cenozoic sunlight shining on ancient forests and mats of algae floating on ancient seas was transformed along with atmospheric CO₂ by photosynthesis into energy laden organic materials. These materials were later deposited and further transformed by geologic processes into what are now called fossil fuels. The ignition and transformation of fossil fuels in the site projects releases the stored ancient sunlight in the form of radiant energy.

The environmental furnace works captured on the video are Untitled (Earth Orchid, (1988)), Oculus: Dead Sea/Oil Field, (1989) and Humboldt Ship, (1989). These are grouped under the title of "51 Million BTU’s" (British Thermal Unit, is a scientific term for the measurement of energy) which is the total calculated energy expended in the firing of these projects. This series in itself makes an initial exploration through form, image and process of the solar/botanical/geologic origin of fossil fuels and the transformative energy released by their ignition. As an example, Untitled (Earth Orchid) examines botanical form by the ignition of natural gas into radiant energy within the central core of a furnace shaped to resemble the cross-section of an abstract orchid.

In a prototype version of 51 Million BTU’s/ Metabolism Study/C₃H₈, e^-, NaCl, 1991-1993, a single three-tube video projector was used to project an interwoven sequence of the furnace firings onto the rock salt screen. The salt crystal screen references the generally marine environment in which botanic materials were originally deposited. The crystals also act as prisms to diffract the projected video image breaking down its visual structure. The projected images underwent a moderate degree of transformation towards sunlight, still retaining some of their form.

A further version of the project proposes using three, 3-tube video projectors also projecting onto a heavily rock salt encrusted screen to completely transform the projected image into a intense undifferentiated light reminiscent of sunlight. Simultaneous sound and image of non-diffracted video would be seen on adjacent monitors so the viewer can see the degree of transformation taking place.

John Roloff, 1999