Actually not the result of stored solar energy, at least not in terms of that energy falling on the Earth.
Its geothermal, meaning it comes from the heat at the Earth' s core. This is released at the joints of geotechnic plates where it vents. Microbes feed off the energy (or more accurately the chemistry that this enables). More sophisticated creatures feed off the microbes. This system is now independent of the sun. If the sun stopped shining, this would carry on.
However, you could argue that, as the Earth was once part of the sun, the origin of the energy remaining in the Earth's core is still ultimately solar...
Either way these bizarre eco systems have been known for many years, and are behind the focus of much exploration / speculation by NASA (for instance of the possibility of life on various geologically active moons in the solar system). In particular this has opened up the possibility that life may exist where there is little light from the sun to fuel it.
