| ▲ | rybosworld 4 hours ago | |
Just so we can agree on numbers for the napkin math - an 8x H200 weighs 130 kg: https://www.nvidia.com/en-eu/data-center/dgx-h200/?utm_sourc... Power draw is max 10.2 kW but average draw would be 60-70% of that. let's call it 6kW. It is possible to obtain orbits that get 24/7 sunlight - but that is not simple. And my understanding is it's more expensive to maintain those orbits than it would be to have stored battery power for shadow periods. Average blackout period is 30-45 minutes. So you'd need at least 6 kWh of storage to avoid draining the batteries to 0. But battery degradation is a thing. So 6 kWh is probably the absolute floor. That's in the range of 50-70 kg for off-the-shelf batteries. You'd need at least double the solar panel capacity of the battery capacity, because solar panels degrade over time and will need to charge the batteries in addition to powering the gpu's. 12 kW solar panels would be the absolute floor. A panel system of that size is 600-800 kg. These are conservative estimates I think. And I haven't factored in the weight of radiators, heat and radiation shielding, thermal loops, or anything else that a cluster in space might need. And the weight is already over 785 kg. Using the $1,500 per kg, we're approaching $1.2 million. Again, this is a conservative estimate and without accounting for most of the weight (radiators) because I'm too lazy to finish the napkin math. | ||
| ▲ | nine_k 2 hours ago | parent [-] | |
I think we're on the same page. Lifting the actual computing devices would be not that expensive, compared to lifting a lot of other related mass, principally the cooling systems, and the solar panels. The solar panels used in space are really lightweight, about 2 kg / m² [1], it's like ten times lighter weight than terrestrial panels. Still they need load-bearing scaffolding, and electrical conductors to actually collect the hundreds of kilowatts. Water can't be made as lightweight though. | ||