Assess Space-Based Solar Power in European-Scale Power System Decarbonization

TL;DR

The paper investigates how space-based solar power (SBSP) could contribute to Europe’s net-zero transition by embedding two NASA-projected SBSP designs into a high-resolution European capacity-expansion and dispatch model. It compares RD1, a near-baseload heliostat swarm with low TRL, and RD2, a partially intermittent planar array with higher TRL, under 2020 and 2050 assumptions. Under NASA’s 2050 projections, RD1 can lower total system costs by about 7–15%, displace up to 80% of intermittent wind and solar, and reduce battery use by over 70%, though long-duration storage remains important for seasonality; RD2 remains economically unattractive. Sensitivity analyses reveal cost thresholds where RD1 shifts from complementary to dominant baseload deployment (roughly 14× and 9× the 2050 PV cost, respectively), while RD2 would require even larger cost reductions (9× to 6×) and would lean on short-duration storage. These results provide quantified techno-economic benchmarks for SBSP and outline pathways for integrating centralized, non-intermittent renewables into Europe’s grid, informing policy and industry decisions on large-scale decarbonization strategies.

Abstract

Meeting net-zero targets remains formidable as terrestrial renewables grapple with intermittency and regional variability. Here, we integrate space-based solar power (SBSP) -- a potential near-constant, orbital solar technology -- into a high-resolution, Europe-wide capacity-expansion and dispatch model to quantify its contribution under net-zero constraints. We examine two advanced SBSP designs: (1) a near-baseload, low Technology Readiness Level (TRL) concept (heliostat-based Representative Design RD1) and (2) a partially intermittent, higher-TRL concept (planar-based RD2), both drawing on NASA's 2050 cost and performance projections. Our results show that RD1 can reduce total system costs by 7--15%, displace up to 80% of intermittent wind and solar, and cut battery usage by over 70%, if it meets its forecast cost reductions -- though long-duration storage (e.g., hydrogen) remains essential for seasonal balancing. By contrast, RD2 is economically unattractive at its projected 2050 costs. Through extensive sensitivity analyses, we identify cost thresholds at which SBSP shifts from cost-prohibitive to complementary and ultimately to a dominant baseload technology. Specifically, RD1 becomes complementary at roughly 14x and dominant at 9x the 2050 solar PV capital cost, benefiting from its continuous power generation. Meanwhile, RD2 must achieve even lower cost levels (9x to be complementary and 6x to dominate) and would rely on short-duration storage to mitigate its partial intermittency. These findings provide quantified techno-economic benchmarks and reveal alternative net-zero pathways, offering critical guidance for policymakers and industry stakeholders seeking large-scale, centrally coordinated renewable solutions with non- or low-intermittency.

Figures (10)

• Figure 1: Overview of SBSP Operational Process and System Architectures.(a) Stepwise operational process of a SBSP system, including: (1) launch and installation in space, (2) solar energy collection, (3) conversion to electricity and then to microwave, (4) transmission to Earth, (5) reception and reconversion on the ground, and (6) grid delivery. (b) Main structures of two representative SBSP system designs. The left panel shows the Innovative Heliostat Swarm concept, which is broadly derived from the Alpha Mark III architecture ref13. This design employs reflectors and a central concentrator to continuously focus sunlight throughout the day, using independently operating hexagonal modules arranged in a beehive-like configuration. The right panel depicts the mature Planar Array system with a sandwich architecture: solar collection on one side and microwave transmission on the other. Identical power modules convert solar energy to microwave power and are wirelessly controlled by a central bus, while Earth-facing antennas maintain orientation via gravity gradient forces in GEO.
• Figure 2: Comparison of the variations in power output per square meter of heliostat design (RD1), planar design (RD2), and terrestrial solar panels in 2020. (a) To clarify the power generation curves of heliostat design, planar design, and terrestrial solar, the hourly data were averaged to obtain daily mean values, enabling the observation of overall trends throughout 2020. (b) Hourly data from July 1 to July 15 represent the summer period. (c) Hourly data from December 1 to December 15 represent the winter period.
• Figure 3: Technology-specific installed capacity and electricity generation across scenarios in 2050. Panels (a) and (b) show installed capacity and electricity generation by technology under 3 market opportunity scenarios with heliostat design (RD1) and planar design (RD2).
• Figure 4: Weekly Power Output Variability of SBSP, Other Renewables and Storage Technologies (Discharging) under Medium SBSP Market Opportunity Scenario in 2050. Panels (a) and (b) present a comparative analysis of heliostat design (RD1) and planar design (RD2), respectively, with Solar, Wind, Hydro, Pumped Hydro Storage (PHS), Battery, and Hydrogen storage, in terms of power output and variability. Solid lines indicate weekly average power, while shaded bands denote the range of weekly maximum and minimum power fluctuations.
• Figure 5: Changes in Installed Capacity in Response to SBSP Capital Costs in 2050. The panel (a) and (b) compares the installed capacities of terrestrial solar, wind, heliostat design (RD1) and planar design (RD2) under varying SBSP capital costs. The x-axis represents the capital cost of SBSP in EUR/kW$\cdot$year, while the y-axis represents the corresponding installed capacity (GW).