New Space based solar power designs can get to less than 2 cents per kwh

John C. Mankins (
Mankins Space Technology) has thoroughly updated his space-based solar power design. The SPS-ALPHA Mark-II design using new technologies improves technical feasibility and economic viability of space solar power.

Additional details of the “SPS-ALPHA Mk-II” will be presented in the second edition of a Mankin book. The book is planned for release in 2018.

* using thin reflectors
* using robotic arms for assembly
* using lower cost launch systems
* improving the module design
* improving the reflector designs to make the system last longer which reduces operating costs

Getting to less than 2 cents per kwh would make it cheaper than coal and natural gas power.

Spacex Falcon 9 block 5 with 10 reuses of the first stage could be half the cost per kilogram versus a single use Falcon 9.

High re-use for first stages for the Falcon 9 block 5 would get its cost to about $1500 per kilogram to low earth orbit.
High re-use for first stages for the Falcon Heavy would get its cost to about $1000 per kilogram to low earth orbit.
The target for the fully re-usable Big Falcon Rocket would potentially $100 per kilogram.

The Falcon 9 Block 5 is expected to be far more reusable than the Block 3. Shotwell said a Block 5 booster could relaunch “ a dozen or so times.” The Block 3, by comparison, has an estimated life of two or three missions.

Shotwell said the Block 5 version of the Falcon 9 won’t need refurbishing, but will mainly undergo inspections prior to launch, streamlining the process compared to the first reused boosters.

Block 5 will feature:

For increased payload:
* 7–8% more thrust by upgrading the engines,
* an improved flight control system for an optimized angle of attack on descent, lowering landing fuel requirements.

For rapid reusability:
* Forged, more temperature-resistant titanium grid fins,
* a thermal protection coating on the first stage to limit reentry heating damage,
* a set of retractable landing legs for rapid recovery and shipping,
* a reusable heat shield protecting the engines and plumbing at the base of the rocket.