Project Brighter than Sunshine: Global Solar Energy Potential at the Land-​​Energy-​​Food Nexus


The need to mit­i­gate cli­mate change, safe­guard energy secu­rity, and increase the sus­tain­abil­ity of human activ­i­ties is prompt­ing a rapid and global tran­si­tion from carbon-​​intensive fuels to renew­able energy (IPCC 2014). Among renew­able energy sys­tems, solar energy has one of the great­est cli­mate change mit­i­ga­tion poten­tials with life cycle emis­sions as low as 14 g CO2–eq KWh–1 (car­bon diox­ide equiv­a­lent per kilo­watt hour; com­pare this to 608 g CO2–eq KWh–1 for nat­ural gas). Solar energy embod­ies diverse tech­nolo­gies able to cap­ture the sun’s ther­mal energy, such as con­cen­trat­ing solar power (CSP) sys­tems, and pho­tons using pho­to­voltaics (PV). Solar energy sys­tems are highly mod­u­lar rang­ing from small-​​scale deploy­ments (≤ 1 megawatt [MW]; e.g., res­i­den­tial rooftop mod­ules, portable bat­tle­field sys­tems, solar water heaters) to cen­tral­ized, utility-​​scale solar energy instal­la­tions (USSE, ≥1 MW) where a large econ­omy of scale can meet greater energy demands. Nonethe­less, the dif­fuse nature of solar energy neces­si­tates that large swaths of space or land be used to col­lect and con­cen­trate solar energy into forms usable for human con­sump­tion, increas­ing con­cern over poten­tial impacts on nat­ural ecosys­tems, their ser­vices, and bio­di­ver­sity therein. For exam­ple, at a capac­ity fac­tor of 0.20, a sin­gle ter­awatt of USSE capac­ity scales to 142,857 km2, roughly the area of the state of New York, USA, pro­vid­ing chal­lenges for the inte­gra­tion of poten­tially mas­sive projects into com­plex and frag­mented landscapes.


The deci­sions humans make about how much land to use, where, and for what end-​​use are dri­vers of Earth sys­tem processes. For exam­ple, chang­ing the use of land or con­vert­ing it from one land-​​cover type to another is a source of green­house gas emis­sions, which are released to the atmos­phere when bio­mass, includ­ing soil, is dis­turbed or removed. How then do we decide when to con­vert a for­est that serves as a car­bon sink into a farm that feeds a com­mu­nity, or a farm into a PV park that elec­tri­fies a rural vil­lage? Inno­va­tion and poli­cies direct­ing sus­tain­able path­ways of land use for energy and food pro­duc­tion can be uti­lized to address an increas­ing global pop­u­la­tion of which 1.5 bil­lion today live with­out access to elec­tric­ity. Energy poverty leads to a loss of human health and well­be­ing and depressed eco­nomic and edu­ca­tional oppor­tu­ni­ties, par­tic­u­larly for women and chil­dren. Our research here is designed to demon­strate, quan­tify, and facil­i­tate the poten­tial of solar energy sys­tems to address global prob­lems related to cli­mate change, energy access, and the sus­tain­abil­ity of food sys­tems, which are inter­con­nected. This research draws from eco­log­i­cal field exper­i­ments, knowl­edge data dis­cov­ery, geo­graphic infor­ma­tion sys­tems, spa­tial and eco­nomic mod­el­ing, and is com­prised of five inter­re­lated projects:

  1. Envi­ron­men­tal co-​​benefits of solar energy
  2. The Energy-​​Food-​​Water Cube: Capa­bil­ity and scal­a­bil­ity in on-​​farm energy production
  3. Global solar energy brightspots: Shin­ning light on the world’s energy insecure
  4. The land-​​energy-​​food nexus in California’s Cen­tral Valley
  5. Lim­its of land: Global esti­mates of land for food and energy