702 watt-hours is about 602 food/kilocalories, and an arbitrary average human needs about 2,000 per day.

If there's something fundamental to machinery in general that makes it consume more energy by weight than a human, than that's probably because machinery is often purpose-built for specific tasks where the task is more important than the energy usage, whereas humans (and living things in general) evolved over a very long time in a way which prioritized surviving to make babies and therefore lower energy usage — needing less food comes in handy. There is likely no way to fix this. If you have a humanoid machine, it's probably made of things which are denser than human tissue and therefore require more energy to move around.

If you need a power source I recommend an improved version of the Advanced Sterling Radioisotope Generator, which, with fresh plutonium-238 fuel bricks, can provide roughly enough power to run a human's base metabolism and is close to (if not quite) small enough to fit in a human-sized humanoid robot's torso. Presumably one designed with technology from perhaps twenty years in the future could be a bit more powerful and a bit less large. It will, however, be very heavy by human standards — 32 kilograms — and it will slowly degrade over time due to the radioactive decay of its fuel. Perhaps the robot gets a visit to the doctor, so to speak, every five years or so, for semi-spent fuel to be removed and fresh plutonium bricks to be inserted.

If you need an energy storage I recommend a flywheel, specifically one made of something very tough, rotating incredibly quickly, suspended by magnets, and inside a sealed-off vacuum chamber to minimize energy losses from aerodynamic drag on the flywheel. Again, the current state-of-the-art isn't really energy-dense enough or small enough to fit in what you seem to be talking about, but it's close enough, and flywheel storages have many advantages over chemical batteries.

I have no idea how much power or energy your robot needs because I have no idea how heavy it is, what type of actuators it uses, etc.

702 watt-hours is about 602 food/kilocalories, and an arbitrary average human needs about 2,000 per day.

If there's something fundamental to machinery in general that makes it consume more energy by weight than a human, than that's probably because machinery is often purpose-built for specific tasks where the task is more important than the energy usage, whereas humans (and living things in general) evolved over a very long time in a way which prioritized surviving to make babies and therefore lower energy usage — needing less food comes in handy. There is likely no way to fix this. If you have a humanoid machine, it's probably made of things which are denser than human tissue and therefore require more energy to move around.

If you need a power source I recommend an improved version of the Advanced Sterling Radioisotope Generator, which, with fresh plutonium-238 fuel bricks, can provide roughly enough power to run a human's base metabolism and is close to (if not quite) small enough to fit in a human-sized humanoid robot's torso. Presumably one designed with technology from perhaps twenty years in the future could be a bit more powerful and a bit less large. It will, however, be very heavy by human standards — 32 kilograms — and it will slowly degrade over time due to the radioactive decay of its fuel. Perhaps the robot gets a visit to the doctor, so to speak, every five years or so, for semi-spent fuel to be removed and fresh plutonium bricks to be inserted.

If you need an energy storage I recommend a flywheel, specifically one made of something very tough, rotating incredibly quickly, suspended by magnets, and inside a sealed-off vacuum chamber to minimize energy losses from aerodynamic drag on the flywheel. Again, the current state-of-the-art isn't really energy-dense enough or small enough to fit in what you seem to be talking about, but it's close enough, and flywheel storages have many advantages over chemical batteries.

I have no idea how much power or energy your robot actually needs (it's probably not going to be comparable to a human) because I have no idea how heavy it is, what type of actuators it uses, etc.

702 watt-hours is about 602 food/kilocalories, and an arbitrary average human needs about 2,000 per day.

If there's something fundamental to machinery in general that makes it consume more energy by weight than a human, than that's probably because machinery is often purpose-built for specific tasks where the task is more important than the energy usage, whereas humans (and living things in general) evolved over a very long time in a way which prioritized surviving to make babies and therefore lower energy usage — needing less food comes in handy. There is likely no way to fix this. If you have a humanoid machine, it's probably made of things which are denser than human tissue and therefore require more energy to move around.

If you need a power source I recommend an improved version of the Advanced Sterling Radioisotope Generator, which, with fresh plutonium-238 fuel bricks, can provide roughly enough power to run a human's base metabolism and is close to (if not quite) small enough to fit in a human-sized humanoid robot's torso. Presumably one designed with technology from perhaps twenty years in the future could be a bit more powerful and a bit less large. It will, however, be very heavy by human standards — 32 kilograms — and it will slowly degrade over time due to the radioactive decay of its fuel. Perhaps the robot gets a visit to the doctor, so to speak, every five years or so, for semi-spent fuel to be removed and fresh plutonium bricks to be inserted.

If you need an energy storage I recommend a flywheel, specifically one made of something very tough, rotating incredibly quickly, suspended by magnets, and inside a sealed-off vacuum chamber to minimize energy losses from aerodynamic drag on the flywheel. Again, the current state-of-the-art isn't really energy-dense enough or small enough to fit in what you seem to be talking about, but it's close enough, and flywheel storages have many advantages over chemical batteries.

702 watt-hours is about 602 food/kilocalories, and an arbitrary average human needs about 2,000 per day.

If there's something fundamental to machinery in general that makes it consume more energy by weight than a human, than that's probably because machinery is often purpose-built for specific tasks where the task is more important than the energy usage, whereas humans (and living things in general) evolved over a very long time in a way which prioritized surviving to make babies and therefore lower energy usage — needing less food comes in handy. There is likely no way to fix this. If you have a humanoid machine, it's probably made of things which are denser than human tissue and therefore require more energy to move around.

If you need a power source I recommend an improved version of the Advanced Sterling Radioisotope Generator, which, with fresh plutonium-238 fuel bricks, can provide roughly enough power to run a human's base metabolism and is close to (if not quite) small enough to fit in a human-sized humanoid robot's torso. Presumably one designed with technology from perhaps twenty years in the future could be a bit more powerful and a bit less large. It will, however, be very heavy by human standards — 32 kilograms — and it will slowly degrade over time due to the radioactive decay of its fuel. Perhaps the robot gets a visit to the doctor, so to speak, every five years or so, for semi-spent fuel to be removed and fresh plutonium bricks to be inserted.

If you need an energy storage I recommend a flywheel, specifically one made of something very tough, rotating incredibly quickly, suspended by magnets, and inside a sealed-off vacuum chamber to minimize energy losses from aerodynamic drag on the flywheel. Again, the current state-of-the-art isn't really energy-dense enough or small enough to fit in what you seem to be talking about, but it's close enough, and flywheel storages have many advantages over chemical batteries.

I have no idea how much power or energy your robot needs because I have no idea how heavy it is, what type of actuators it uses, etc.