An open innovation challenge designed to reduce the amount of sand used in hydraulic fracturing operations has selected five winning sand alternatives.

Hosted by GE and energy company Statoil, the challenge was designed to find alternatives to transporting sand, which is used to open fractures and encourage the free flow of oil and gas, thereby minimizing its impact on the environment.

Among the winning submissions were Bioastra, which used biopolymers from the medical industry that can change from liquid to solid in response to temperatures and other factors.

According to the company, the lightweight composite particles can swell up to 10 times their original size in liquid and can fit into fissures and conform to small cracks.

"We are working on things such as injectable implants that respond to external stimuli like temperature, and change from liquid to solid in the body," Bioastra founder and CEO Sumitra Rajagopalan said. "But to be honest, the material doesn't care whether you put it inside the body or inside an oil well."

Other winning submissions in addition to Bioastra include: Semplastics, developers of a liquid polymer that is cured to a solid state and then fired to create small, spherical particles with half the density of sand; Biopolynet, which has created a coiled biopolymer fluid additive that increases viscosity and stickiness; University of North Dakota Energy & Environmental Research Center, which has devised a proppant that uses local non-premium ore source rock rather than ceramics with high alumina content typically sourced far from the oil and gas basins; and Hoowaki with its alumina ceramic x-shape proppant.

Each wining submission will earn a cash prize of $25,000 and will be eligible to receive additional funding from a prize pool of $375,000 for potential development or commercialization of the technology.

To learn more about the challenge and the winners, go to Statoil.