  Information engines can convert thermal fluctuations of a bath at temperature
$T$ into work at rates of order $k_\mathrm{B}T$ per relaxation time of the
system. We show experimentally that such engines, when in contact with a bath
that is out of equilibrium, can extract much more work. We place a heavy,
micron-scale bead in a harmonic potential that ratchets up to capture favorable
fluctuations. Adding a fluctuating electric field increases work extraction up
to ten times, limited only by the strength of applied field. Our results
connect Maxwell's demon with energy harvesting and an estimate of efficiency
shows that information engines in nonequilibrium baths can greatly outperform
conventional engines.
