The article presents a reasonably good analysis of the problem however it makes a few incorrect conclusions that are commonly seen.
Firstly, if comparisons are to be made, it is important to compare like for like, e.g. the LCOE of intermittent solar cannot be compared directly with a firm source like space solar with a conclusion that space solar is not competitive if the LCOE is higher than ground solar. This is because the value to the end user (industry, governments) of an unrealiable generation source is not the same (i.e. lower) than a reliable one. Therefore, full-system LCOE is required to be estimated, which for ground solar would need to account for the firming and additional distribution costs incurred to improve its reliability. This adds substantial costs to ground solar at system-level (overbuild, storage, grid-expansion, gas backup) easily doubling it or more, see Lazard and other such analyses), which is becoming increasing apparent in countries where solar/wind have high degrees of penetration into the grid. This is just the financial cost, and doesn't account for the environmental costs of implementing all of that. It's also important to recognise that at nation state level, governments setting energy policy have to balance a variety of factors and are not just driven by pure LCOE metrics in decision making on the future energy mix. In the end, we need to solve the Energy Trilemma, i.e. balancing energy security, environmental sustainability and affordability. One or only two out of the three, it not enough if we are to truly solve the challenge ahead.
Secondly, the latter part of the article discusses that initial deployment of SBSP will have high LCOE compared to incumbent technologies and therefore not be economically competitive at a global scale. It is indeed likely that it will be more expensive than some other energy sources initially, but this is fully consistent with the introduction of new technologies in the early stages. It was no different with wind and solar which were also expensive when first employed. In order for them to compete economically on their own, they both required substantial public support through subsidies and incentives to get a foothold in the market globally and reach a scale that allowed that. It will likely be the same with SBSP as long as the long-term economic/environmental potential (+ ancillary benefits) are seen as justifying the support for introduction of this new technology into the future energy mix, alongside all the other sources.
Decarbonisation of societies is an urgent imperative globally, and given SBSPs potential to significantly accelerate these efforts, it does not make sense to only focus on short term, small scale applications while losing momentum on pursuing the much needed large scale applications. Of course, early (smaller) applications have their value as sources of early returns of investment for some investors and they definitely can help de-risk the larger applications.
Thank you for such a thoughtful and detailed comment. It’s always great to see deeper engagement with the topic, especially from someone well-informed about the energy sector. As we mentioned in the article, there is little space to explore all the potential metrics and pricing factors in our publishing format, and we’re genuinely glad that the comments section allows us to expand on these, thanks to engaged readers like you.
You’re absolutely right that LCOE, when applied to ground-based solar, can underestimate the real system cost, especially when regional variability and distribution infrastructure are factored in.
At the same time, we’d point out that our analysis also ignored many costs that SBSP would incur, such as long-term maintenance in orbit, rectenna CAPEX and maintenance, or additional regulatory overhead. In that sense, it’s fair to say we’re comparing minimum-to-minimum — not exactly apples-to-apples, but some approximation to this. The intent was to use LCOE not as a definitive answer but as a preliminary tool to open the conversation — and for that, it still has value. After all, even NASA uses LCOE as a starting point in their assessments: https://www.nasa.gov/wp-content/uploads/2024/01/otps-sbsp-report-final-tagged-approved-1-8-24-tagged-v2.pdf
We also fully agree with your point about the early cost disadvantage of new technologies, and we hope SBSP will follow a similar trajectory to wind and solar. The article doesn’t argue against long-term SBSP investment; rather, it emphasizes the importance of acknowledging bottlenecks today so we can collectively work through them as the field matures. Small-scale applications shouldn’t come at the expense of larger ambitions — both are essential. Early projects can help de-risk technology and build investor and public confidence, serving as critical stepping stones to the broader, transformational impact SBSP could have.
Thanks again for contributing such a valuable perspective. These conversations are exactly what help move the industry forward, and we hope to keep the dialogue going! If you have any thoughts regarding SBSP to publish in our blog, you are welcome to collaborate: ivan@spaceambition.org
The value of continuous (baseload) and dispatchable power is overlooked in this article. Imperial College London has completed a study of the UK energy system with and without SBSP. It shows that for every 2 GW of SBSP, there are annual savings of over £1Bn, and these savings scale with increasing SBSP capacity. It reduces the need to over build wind and solar capacity, reduces the need for other backup and storage, and greatly reduces the need to expand the grid transmission system. It also provides export revenues without costly interconnector cables.
As a standalone baseload energy technology, SBSP will be highly competitive but as part of the whole energy system its value is massive in delivering abundant affordable and reliable energy.
Thank you for your valuable comment. It is indeed true that SBSP stands out from the rest of energy sources in terms of its continuity. Unfortunately, today no one can say with certainty how much this energy will cost because no one has ever built a structure of such dimensions in orbit. For sure, you can accurately calculate the value of the baseload power for the grid, but on top of that there will be a high upfront cost and we are still to learn what it is going to be.
This post is disappointing both in terms of journalistic accuracy,and from a lack of understanding of LCOE and how it applies to SBSP. LCOE does NOT apply accurately with respect to intermittent renewables but again, I am disappointed about your post and lack of analytical perspective. It’s not like you as far as I know.
Keep in mind that our goal is to develop an interest in spacetech among the broadest possible audience. Therefore, the format of the articles does not imply an exhaustive study in one post. Most readers simply will not be able to focus on 10+ minutes of reading. We agree that LCOE is not a gold standard metric, as we carefully indicated in the text. We will certainly continue to cover SBSP to describe many of its aspects in short articles like this one over time. We will be glad if you remain our regular reader and critic (in a good sense of that :) ). In the meantime, for exhaustive studies that take into account all aspects of solar energy, we refer the reader to specialized studies to which we provide links in the text. Some of them are summarised here: https://www.aerosociety.com/media/23706/efs-d1-peter-entwistle.pdf
Two things. The wireless power transfer is not a new technology, it sits in every communication device globally (ie your cell phone in your pocket). The beam forming and aiming is already demonstrated at scale with cell phone towers. Obviously SBSP is bigger, but simpler since the antennas are not 2-way data transfer devices. Second, the firming costs of terrestrial solar are non-trivial - every market with significant solar penetration sees higher total cost of energy (LCOE + firming) with many markets at $350+/MWh. SBSP is closer than anyone suspects - able to achieve total cost of energy lower than any other source on the planet.
We agree that the transmission of electromagnetic energy at a distance is a technically absolutely solved problem. This is a huge advantage of SBSP over, for example, thermonuclear fusion. However, now the bottleneck is not in technical feasibility, but in economics and efficiency. The mobile phone in your pocket is not designed for efficient energy transfer from point to point. In beam forming applications, directed energy transfer is considered successful if its efficiency has reached a few percent. Kilometer-scale antennas can, in principle, allow an efficiency of about 30%, which is included in the specialized studies to which we refer. However, I want to emphasize that technically they have never been made yet. In outer space, it is very difficult to build a rigid and at the same time lightweight kilometer-sized structure that will exclude centimeter-size deformations. However, this is extremely important for maintaining the beam direction and high transmission efficiency. Our estimates (we have not provided them here, since this is a short article format) show that if the transmission efficiency is less than 20%, the economic justification of energy is impossible at any cost of delivering the payload and at any cost of solar panels.
We are eager to witness such constructions and will closely monitor any attempts to build something like this. Even in adjacent sectors such as communications.
I would agree that economics would struggle at low transfer efficiency - but I would offer that many studies from the last 40+ years describe that high efficiency RF wireless power transfer is technically feasible and address the flatness and mass concerns of the transmitter. NASA's own internal study from Jan. 2024 describes efficiency levels for the most conservative set of assumptions as ~84% for the RF-RF portion (Appendix B of study, linked below):
The following is a summary of major losses of efficiency for each functional step:
• Collect: solar cell efficiency (35%)
• Convert in-space: solar energy to microwave radiation (DC-DC 90% and DC-RF 70%)
If you account for everything end-to-end efficiency is 12% (solar to DC on ground) - which is actually not bad for a clean, firm power source with no feedstock costs. The range of assumptions in the NASA study are interesting - with the baseline being the worst of worst (shown in Fig. 3) with LCOE at $600/MWh. But in those range of assumptions is a combination that actually make SBSP the best of best LCOE for solving the world's energy challenges at <$8/MWh.
There are several businesses commercializing this opportunity globally - as the economics are compelling.
The article presents a reasonably good analysis of the problem however it makes a few incorrect conclusions that are commonly seen.
Firstly, if comparisons are to be made, it is important to compare like for like, e.g. the LCOE of intermittent solar cannot be compared directly with a firm source like space solar with a conclusion that space solar is not competitive if the LCOE is higher than ground solar. This is because the value to the end user (industry, governments) of an unrealiable generation source is not the same (i.e. lower) than a reliable one. Therefore, full-system LCOE is required to be estimated, which for ground solar would need to account for the firming and additional distribution costs incurred to improve its reliability. This adds substantial costs to ground solar at system-level (overbuild, storage, grid-expansion, gas backup) easily doubling it or more, see Lazard and other such analyses), which is becoming increasing apparent in countries where solar/wind have high degrees of penetration into the grid. This is just the financial cost, and doesn't account for the environmental costs of implementing all of that. It's also important to recognise that at nation state level, governments setting energy policy have to balance a variety of factors and are not just driven by pure LCOE metrics in decision making on the future energy mix. In the end, we need to solve the Energy Trilemma, i.e. balancing energy security, environmental sustainability and affordability. One or only two out of the three, it not enough if we are to truly solve the challenge ahead.
Secondly, the latter part of the article discusses that initial deployment of SBSP will have high LCOE compared to incumbent technologies and therefore not be economically competitive at a global scale. It is indeed likely that it will be more expensive than some other energy sources initially, but this is fully consistent with the introduction of new technologies in the early stages. It was no different with wind and solar which were also expensive when first employed. In order for them to compete economically on their own, they both required substantial public support through subsidies and incentives to get a foothold in the market globally and reach a scale that allowed that. It will likely be the same with SBSP as long as the long-term economic/environmental potential (+ ancillary benefits) are seen as justifying the support for introduction of this new technology into the future energy mix, alongside all the other sources.
Decarbonisation of societies is an urgent imperative globally, and given SBSPs potential to significantly accelerate these efforts, it does not make sense to only focus on short term, small scale applications while losing momentum on pursuing the much needed large scale applications. Of course, early (smaller) applications have their value as sources of early returns of investment for some investors and they definitely can help de-risk the larger applications.
Thank you for such a thoughtful and detailed comment. It’s always great to see deeper engagement with the topic, especially from someone well-informed about the energy sector. As we mentioned in the article, there is little space to explore all the potential metrics and pricing factors in our publishing format, and we’re genuinely glad that the comments section allows us to expand on these, thanks to engaged readers like you.
You’re absolutely right that LCOE, when applied to ground-based solar, can underestimate the real system cost, especially when regional variability and distribution infrastructure are factored in.
At the same time, we’d point out that our analysis also ignored many costs that SBSP would incur, such as long-term maintenance in orbit, rectenna CAPEX and maintenance, or additional regulatory overhead. In that sense, it’s fair to say we’re comparing minimum-to-minimum — not exactly apples-to-apples, but some approximation to this. The intent was to use LCOE not as a definitive answer but as a preliminary tool to open the conversation — and for that, it still has value. After all, even NASA uses LCOE as a starting point in their assessments: https://www.nasa.gov/wp-content/uploads/2024/01/otps-sbsp-report-final-tagged-approved-1-8-24-tagged-v2.pdf
We also fully agree with your point about the early cost disadvantage of new technologies, and we hope SBSP will follow a similar trajectory to wind and solar. The article doesn’t argue against long-term SBSP investment; rather, it emphasizes the importance of acknowledging bottlenecks today so we can collectively work through them as the field matures. Small-scale applications shouldn’t come at the expense of larger ambitions — both are essential. Early projects can help de-risk technology and build investor and public confidence, serving as critical stepping stones to the broader, transformational impact SBSP could have.
Thanks again for contributing such a valuable perspective. These conversations are exactly what help move the industry forward, and we hope to keep the dialogue going! If you have any thoughts regarding SBSP to publish in our blog, you are welcome to collaborate: ivan@spaceambition.org
The value of continuous (baseload) and dispatchable power is overlooked in this article. Imperial College London has completed a study of the UK energy system with and without SBSP. It shows that for every 2 GW of SBSP, there are annual savings of over £1Bn, and these savings scale with increasing SBSP capacity. It reduces the need to over build wind and solar capacity, reduces the need for other backup and storage, and greatly reduces the need to expand the grid transmission system. It also provides export revenues without costly interconnector cables.
As a standalone baseload energy technology, SBSP will be highly competitive but as part of the whole energy system its value is massive in delivering abundant affordable and reliable energy.
Hi Martin,
Thank you for your valuable comment. It is indeed true that SBSP stands out from the rest of energy sources in terms of its continuity. Unfortunately, today no one can say with certainty how much this energy will cost because no one has ever built a structure of such dimensions in orbit. For sure, you can accurately calculate the value of the baseload power for the grid, but on top of that there will be a high upfront cost and we are still to learn what it is going to be.
Francois,
This post is disappointing both in terms of journalistic accuracy,and from a lack of understanding of LCOE and how it applies to SBSP. LCOE does NOT apply accurately with respect to intermittent renewables but again, I am disappointed about your post and lack of analytical perspective. It’s not like you as far as I know.
Sorry to disappoint you, Bryan.
Keep in mind that our goal is to develop an interest in spacetech among the broadest possible audience. Therefore, the format of the articles does not imply an exhaustive study in one post. Most readers simply will not be able to focus on 10+ minutes of reading. We agree that LCOE is not a gold standard metric, as we carefully indicated in the text. We will certainly continue to cover SBSP to describe many of its aspects in short articles like this one over time. We will be glad if you remain our regular reader and critic (in a good sense of that :) ). In the meantime, for exhaustive studies that take into account all aspects of solar energy, we refer the reader to specialized studies to which we provide links in the text. Some of them are summarised here: https://www.aerosociety.com/media/23706/efs-d1-peter-entwistle.pdf
Two things. The wireless power transfer is not a new technology, it sits in every communication device globally (ie your cell phone in your pocket). The beam forming and aiming is already demonstrated at scale with cell phone towers. Obviously SBSP is bigger, but simpler since the antennas are not 2-way data transfer devices. Second, the firming costs of terrestrial solar are non-trivial - every market with significant solar penetration sees higher total cost of energy (LCOE + firming) with many markets at $350+/MWh. SBSP is closer than anyone suspects - able to achieve total cost of energy lower than any other source on the planet.
Thank you for your comment! Good point.
We agree that the transmission of electromagnetic energy at a distance is a technically absolutely solved problem. This is a huge advantage of SBSP over, for example, thermonuclear fusion. However, now the bottleneck is not in technical feasibility, but in economics and efficiency. The mobile phone in your pocket is not designed for efficient energy transfer from point to point. In beam forming applications, directed energy transfer is considered successful if its efficiency has reached a few percent. Kilometer-scale antennas can, in principle, allow an efficiency of about 30%, which is included in the specialized studies to which we refer. However, I want to emphasize that technically they have never been made yet. In outer space, it is very difficult to build a rigid and at the same time lightweight kilometer-sized structure that will exclude centimeter-size deformations. However, this is extremely important for maintaining the beam direction and high transmission efficiency. Our estimates (we have not provided them here, since this is a short article format) show that if the transmission efficiency is less than 20%, the economic justification of energy is impossible at any cost of delivering the payload and at any cost of solar panels.
We are eager to witness such constructions and will closely monitor any attempts to build something like this. Even in adjacent sectors such as communications.
I would agree that economics would struggle at low transfer efficiency - but I would offer that many studies from the last 40+ years describe that high efficiency RF wireless power transfer is technically feasible and address the flatness and mass concerns of the transmitter. NASA's own internal study from Jan. 2024 describes efficiency levels for the most conservative set of assumptions as ~84% for the RF-RF portion (Appendix B of study, linked below):
The following is a summary of major losses of efficiency for each functional step:
• Collect: solar cell efficiency (35%)
• Convert in-space: solar energy to microwave radiation (DC-DC 90% and DC-RF 70%)
• Transmit: antenna emission (90%), atmospheric travel (98%), and beam collection (95%)
• Receive: rectenna array reception (78%)
• Convert on-ground: DC-DC (90%)
If you account for everything end-to-end efficiency is 12% (solar to DC on ground) - which is actually not bad for a clean, firm power source with no feedstock costs. The range of assumptions in the NASA study are interesting - with the baseline being the worst of worst (shown in Fig. 3) with LCOE at $600/MWh. But in those range of assumptions is a combination that actually make SBSP the best of best LCOE for solving the world's energy challenges at <$8/MWh.
There are several businesses commercializing this opportunity globally - as the economics are compelling.
We keep a copy of NASA's 2024 SSP report here (as OSTP as an org was recently eliminated): https://drive.google.com/file/d/1gsc2VlbXXyvIwzIHv5gPFWyNviiyE5le/view?usp=drive_link
Thank you for so many details! If you have any thoughts regarding SBSP to publish in our blog, you are welcome to collaborate: ivan@spaceambition.org