Strontium-90 is used in remote arctic weather stations to provide heat to thermoelectric power generators.
One of these generators contains 840 g of strontium-90 when it is commissioned.
One gram of strontium-90 has a power density of 0.46 W/g.
Strontium-90 has a half-life of 28.8 years28.8\text{ years}28.8 years.
Calculate the average energy released per second by the generator after 86.4 years86.4\text{ years}86.4 years.