At Stanford's Celebrating Sustainability Festival on April 22 - Earth Day - Woods researchers demonstrated a range of breakthrough environmental work ranging from virtual reality to mobile toilets.

The free event, held in the Science and Engineering Quad, educates members of the campus community about Stanford's sustainability achievements and opportunities for individual action.

Exhibits that Woods featured at the fair:

Can Virtual Reality Make You Care More About the Earth?

Stanford’s Virtual Human Interaction Lab (VHIL) is helping people learn about climate change and reexamine their use of energy and natural resources. Using avatars and virtual reality simulations, VHIL can more clearly connect people’s energy use with its environmental consequences.

One study showed that when subjects were forced to saw down virtual trees, they later (in the physical world) used fewer paper towels to clean up a spill. Similarly, VHIL simulations can uniquely portray climate change by making the invisible (such as carbon molecules) visible and showing the passage of centuries in moments. With U.S. Department of Energy funding, VHIL researchers are working on simulations to reduce the amount of heat and water people use during showers.

For more information, visit the VHIL website or contact Cody Karutz at

Wastewater Rocket Science

What do rocket science and wastewater treatment have in common? A lot, actually. Rockets get their thrust power from the chemical energy in bonds of fuels. Wastewater treatment facilities can do the same thing by exploiting chemical energy in waste stream molecules. And most waste streams have a lot of potential energy.

In wastewater treatment, bacteria can be used to convert organic matter into methane, a combustible fuel that can then be burned to generate power. It turns out the bacteria in wastewater are also capable of converting waste nitrogen into nitrous oxide – the “laughing gas” used by dentists and fuel used in racecar engines and rockets. Researchers at Re-inventing America’s Urban Water Infrastructure (ReNEWIt) at Stanford University are developing a way to enable energy recovery from both waste carbon and nitrogen. Soon, they may be able to provide lots of free, clean energy from sewage treatment plants.

Read more about the project or contact Yaniv Scherson ( or Meng Ye (

Plastic From Waste Gas

Plastics occupy a fifth of U.S. landfill space. Only 7 percent of plastic resins are recycled, and plastic debris fields spread across millions of square miles of ocean. Currently available biodegradable plastics are produced from agricultural feedstocks that require substantial amounts of arable land, energy, water, fertilizer, pesticide and herbicide.

Stanford researchers have found that by using methane gas to produce the biodegradable polymer polyhydroxybutyrate (PHB), they could solve these issues. Methane is inexpensive and widely available. It’s produced from organic waste in landfills and anaerobic digesters. PHB can be produced naturally by methane-consuming bacteria. PHB can be chemically modified or blended for a variety of uses ranging from food containers to building materials. At the end of its useful life, the plastic can be degraded anaerobically using existing technology, creating additional methane for energy and polymer production – a cradle-to-cradle solution.

Learn more about the project or contact Eric Sundstrom at

Toilet Technology

Around the world, 2.6 billion people lack access to safe sanitation. Researchers working with the Water, Health and Development (WHD) program at the Stanford Woods Institute for the Environment are developing a low-cost mobile toilet that solves the challenge of delivering hygienic household sanitation to residents of dense urban slums. Normally, slum residents choose between open defecation, crowded public toilets or expensive private pit latrines that can't be emptied safely in the narrow alleys.

A solution: low-cost toilets that separate solid and liquid waste into sealable containers that are regularly removed by a service which recovers resources such as compost from the waste. Customers can subscribe to the toilet service instead of buying a toilet at a prohibitive up-front price, and they can take their toilet with them when they move.

After nine months of prototyping and testing in Haiti, WHD researchers deployed toilets to 132 households for a pilot phase. They are currently analyzing survey results from this pilot to assess the impacts of the service on participants' sanitation-related practices, preferences and costs, while also assessing the service’s effectiveness at removing waste from the community.

For more information, visit the WHD website or contact Sebastien Tilmans at

Tough-Guy Corals

The onslaught of climate change makes it imperative to understand how corals – crucial sources of sustenance and livelihoods for more than a billion people – respond to extreme temperatures and other environmental stresses. So Steve Palumbi, a senior fellow at the Stanford Woods Institute for the Environment, set out to learn why some corals die when subjected to warmer water while others survive.

Studying shallow-reef corals off Ofu Island in American Samoa, Palumbi and other researchers examined the corals’ gene expression when they were subjected to water temperatures up to 95 degrees Fahrenheit. Heat-resistant and heat-sensitive corals had a similar reaction to experimental heat, turning on hundreds of genes to reduce or repair damage. However, the heat-resistant corals had these genes already turned on and ready to work even before heat stress began.

DNA sequencing can offer broad insights into the differences that may allow some organisms to persist longer amid future changes due to climate change. Finding coral species that are most likely to endure higher temperatures – “resilience mapping” – is the first step toward protecting them, Palumbi says.

For more information, see