# Ever cheaper energy, advancing technology will perpetually drop the costs for space

Andy Weir who wrote the Martian has now written about a future lunar city in his new book Artemis.

Weir started with a basic question: Why would anybody go to the trouble of building a town on the moon in the first place. To him it had only one workable answer: tourism

Weir assumes that future space flight gets to the same fuel to overhead ratio as a modern airline.

* Rocket 165,500kg (dry weight) that can carry 550 passengers

The 2002 dollars into 2015 dollars and got \$0.93/kg. As for oxygen, I used the publicly available data on what NASA pays for it — \$0.16/kg in 2015 dollars. The reaction requires one part hydrogen and eight parts oxygen (by mass), so the total fuel cost is \$0.245/kg.

They need 12.04kg of fuel for every 1kg we want to put into LEO. Putting 215,000kg into LEO, would require 2,594,620kg of fuel.

Using calculated fuel cost (\$0.245/kg) that means the total fuel cost for the launch is \$637,200.

Now I get to use my airline fuel overhead figure. Airlines have 16.5% fuel overhead ratio and we’re going to assume the space industry will as well. So \$637,109 is 16.5% of our total ticket take. And that means our total take is \$3,861,266.

Weir calculates \$7000 per person to the moon and \$35 per kilogram for cargo.

Greater efficiencies and cost savings can at least halve the cost of hydrogen over the next 20 years

Hydrogen and fuel costs could be brought down from Weir analysis.

The cost of the hydrogen is currently based on the fossil fuel costs of energy to produce the hydrogen. There are papers where solar power is used to produce hydrogen.

Bjørn Simonsen of NEL Hydrogen makes the case for todays cost of solar to produce low cost hydrogen.

If you look at the price at which hydrogen is competitive with gasoline, it is at roughly \$7 per kilo at the pump. To produce 1 kilo of hydrogen, you need roughly 50 kWh of energy, or electricity. And with the price below \$50/MWh, we can make a feasible business case, including all capital investments from the production of hydrogen to the pump at the station.

The levelized cost of solar is down to \$0.03/kWh for some solar plants. What is the most important thing for hydrogen from solar — what is the LCOE from this plant? And the utilization factor. So if we are below \$0.05/kWh, they can make a business case that is attractive.

The cost for solar is already at \$43/MWh and some projects are at about 2 cents per KWh.

French Energy company expects 1 cent per KWh by 2025 and is investing billions based upon that projection

Prices will still fall in half again by 2025 because of scaling efficiency and incremental technological improvements.

The former French gas monopoly (Engie), which is now the world’s largest non-state power producer following a decade of acquisitions, is investing in renewables while selling coal-fired plants and exploration assets to shield itself from commodity-price swings. It plans to spend 1.5 billion euros (\$1.57 billion) by 2018 on technologies including grid-scale battery storage, hydrogen output, “mini-grids” that serve small clusters of homes, and smart buildings that link up heating, lighting and IT systems to save energy and cut costs.

The cost of solar power will probably drop below \$10 a megawatt-hour before 2025 in the world’s sunniest places, according to Lepercq.

There will continue to be a downward spiral in energy costs. Lower energy costs enable new energy to be produced more cheaply.

Lower energy costs overall would also drive down hydrogen and rocket fuel costs.

Momentum Exchange Tethers could be used to save on fuel costs

We do not currently have the materials for space elevators. But we can make lunar space elevators and we can make rotating tethers to boost slower cargo into orbit to save on fuel. We can also use rotating tethers to boost cargo to higher orbits and even the moon without using fuel.

Beyond tourism – massive mining and developing the moon and space

We can build massive things on the moon.

The Aitken basin on the moon measures 2,500 kilometers (1,600 miles) across and is the largest, deepest and oldest basin on the Moon.
There are other large craters.

We can have vehicles and machines shape moon craters into spherical or parabolic shapes for massive telescopes.
We then have vehicles that spray reflective materials or place mirrors onto shaped craters.

Massive telescope observatories in space or on the moon or other areas could observe exoplanets and other objects in super high resolution. There would be massive construction and requirements for a lot of mining of materials.

Even with a lot of robots and automation, there would likely be the justification to have some staffing if large parts of the moon are developed.

Australia still has about 200,000 mining jobs even with a lot of automation. Even if it was ten times more efficient, there could be the need for 20,000 miners and construction workers and technicians and astronomers on the moon.

Staging and transit to the rest of the solar system

With large development of the asteroids and solar system, the near earth area of space would transit, staging areas and support infrastructure for outer space operations.

If you develop massive solar collecting arrays, laser launch arrays and other infrastructure for rapid solar system movement and for collection and processing of space materials, then the space economy would be huge.

Development of space will be non-static

The development of the new world from 1500-1900 was not just for tourism it was built up into large economies. Even Australia with large areas of wasteland ended up supporting over 20 million people.