Even without the billion-plus people who still lack access to electricity, global electrical networks are under considerable stress. The aging and unreliable U.S. power grid strains to keep up with Americans’ increasing appetite for electricity. Gretchen Bakke, author of The Grid: The Fraying Wires Between Americans and Our Energy Future (Bloomsbury, 2016), has argued that the grid's near-obsolescence makes it the “weakest link” in achieving our energy aspirations.
One of the more taxing demands on the grid is lighting. Despite recent improvements in energy efficient sources, such as LEDs, lighting consumes 15 percent of worldwide energy and is responsible for 5 percent of global greenhouse gas emissions, according to a Department of Energy report.
Such concerns have long motivated the work of Sheila Kennedy, FAIA, of Boston-based Kennedy & Violich Architecture. Kennedy’s experiments with materials as vehicles for low-power light sources have resulted in innovative solar textiles, sunlight-delivery systems, and the Portable Light project, a mobile, solar-powered illumination solution for communities lacking access to electricity. Her latest effort, developed in collaboration with MIT chemical engineering professor Michael Strano, utilizes plants as the light delivery mechanism.
Currently on display at the Cooper Hewitt 2019 Design Triennial, the Plant Properties project utilizes biocompatible, GMO-free techniques to generate ambient lighting with live plants, transforming living foliage into a zero-energy light source. Kennedy has long been exploring the implications of this biodesign approach to illuminating the constructed environment. According to the project statement, “The Plant Properties installation demonstrates the architecture of a post-electric, vegetal future when people depend upon living plants for oxygen, water remediation, and ambient light.” Plant Properties depicts the reconfiguration of an New York City brownstone to support the cultivation of light-emitting plants.
Strano’s Light Emitting Plant (LEP) technology is not the only instance of this approach. In 2010, molecular biologist Alexander Krichevsky genetically modified ornamental tobacco plants by introducing autoluminescent marine bacteria into chloroplast DNA. The same year, physicist Yen-Hsun Su, of the Research Center for Applied Science at the Academia Sinica in Taiwan, implanted Bacopa caroliniana plants with gold nanoparticles. When exposed to UV illumination, the plants fluoresced purple light.
The LEP method is distinct from these approaches in several ways: It does not involve genetic modification, like Krichevsky’s process, nor does it require the use of precious metals and UV light. Rather, LEP is based on the injection of a phosphor compound containing firefly luciferase into watercress plants. This compound has an extremely low level of toxicity and is safe enough to be approved for medical procedures, according to Kennedy. "Centralized power systems are incredibly harmful and wasteful, but they’ve been a part of our modern life for so long they go unquestioned for the most part," she tells ARCHITECT. "Even architects might not understand that a typical fluorescent light in an office workplace contains far more toxicity than a nanobionic plant.” The phospshor must be injected into each living plant individually and is not transferred via reproduction. Once a plant dies, it no longer emits light.
The architectural implications of Plant Properties are profound and invite thoughtful consideration. Nanobionic plants are not surrogates for conventional light sources; the illumination has a different intensity and quality from standard light fixtures. However, the delicate, ambient glow they emit is “bright enough to illuminate numbers and large text,” Kennedy says, making them a more than adequate replacement for a nightlight. In experiments to date, watercress plants can emit just over 15 percent the light of commercial-grade LEDs, for up to 21.5 hours in duration. Chromatically, the soft green phosphorescence is influenced by the plant’s chlorophyll. Kennedy and Strano argue that light has assumed various colorations throughout history based on the technology employed, from the reddish hue of candlelight to the cold blue of modern fluorescent light. “It may be in this future that light evolves takes on a greener cast,” Kennedy speculates.
To phosphoresce optimally, the plants need direct access to sunlight. They also require soil, gravity-recycled water, natural ventilation, and access from pollinators—provisions not all buildings offer in adequate supply. Typically, plants are made to conform to the particular conditions and geometries of architecture—think living walls or green roofs configured late in the design process. “Nanobionic plants are 'disobedient’ to these geometries, and in order for people to benefit from their light, the plants need to be able to thrive inside buildings, not along their edges,” Kennedy says.
In this way, the LEP research could inspire not only a new illumination approach but an entirely novel paradigm for architecture based on deep connections to natural systems and the rigorous adherence to natural principles. “We propose an architecture that enables plants to thrive with only natural forces,” Kennedy says. “Wild growing plants within architecture are transgressive and disrupt architecture’s tidiness, scale, and its interior figuration of spaces.” Repetitive, homogeneous, deep floor plates are out; double-height spaces, mirrored heliostats, vertical shafts, and zones for composting and soil reserves are in.
The Plant Properties vision is a radical proposal for a more intimate and appropriately calibrated relationship between people and the natural world. “Diverse human civilizations have been enabled by plant cultivation, but in the modern era, humans have lost touch with plants,” Kennedy says. “The most significant consequence of the introduction of wild growing plants in architecture is a renewed sense of interdependency and partnerships among plants and people.”
