Researchers at the National Renewable Energy Laboratory (NREL) announced that they have figured out a pathway for dealing with the heat loss problem by deploying hot-carrier technology in perovskite solar cells. Hot carrier solar cells offer simplicity of design, low cost, and high efficiency, but are a long way from being commercialized, as one big challenge is revving up the kinetic energy transfer in order to prevent energy loss.
This recent study provides a pathway for pushing perovskite levels upwards, possibly as high as 66%. It determines that charge carriers created by absorbing sunlight by the perovskite cells encounter a bottleneck where phonons (heat carrying particles) that are emitted while the charge carriers cool cannot decay quickly enough. Instead, the phonons re-heat the charge carriers, thereby drastically slowing the cooling process and allowing the carriers to retain much more of their initial energy for much longer periods of time. This potentially allows this extra energy to be tapped off in a hot-carrier solar cell.