While Elon has some strong points about solar energy and battery systems, he doesn’t understand the real drivers for fusion energy.
The Fusion Report has had its numbers of disagreements with Elon Musk, many of which we have covered in our articles. From putting data centers into space to (what we see as) missteps with Tesla, not to mention the joke known as the “Department of Government Efficiency”, we have disagreed with Elon more than we agreed with him. Also, let’s remember that Elon’s company Tesla is in the solar and battery energy storage system (BESS) business, with revenue in Q2 2026 of $3.1B, a capex spend of more than $25B/year on solar cells/panels and Megapack (battery wall) fabrication facilities, and a debt bet of up to $30B. However, we do agree strongly with Elon on the potential for solar energy/BESS technology, especially the relative ease of deploying solar and BESS, assuming that geography is well suited to solar, such as the US southwest (California, Arizona, Nevada), followed by Texas and the US southeast (Florida, North Carolina, Virginia, Georgia). However, we do disagree with Elon’s view that solar energy can replace the use case for fusion energy, so let’s jump right into it.
Elon Musk’s (And TFR’s) Views On Commercial Fusion Energy
In Elon Musk’s view, he doubts that commercial fusion energy will be economically competitive, though he does not necessarily oppose the concept of fusion energy research. Elon has stated that commercial fusion reactors will be extremely expensive and difficult to build, fuel, maintain, and operate, and that their electricity would likely be more expensive than solar power paired with BESS technology. Musk’s preferred alternative is to harness the “enormous, free fusion reactor in the sky” (the Sun) through solar generation, storage, and transmission infrastructure. In 2021, he also said that fusion energy was “not a necessity,” as Musk postulated that very safe nuclear fission reactors (which are neither cheap nor truly clean) could provide reliable and clean energy. More recently, he has criticized efforts to build small terrestrial fusion reactors as wasteful unless they are explicitly treated as scientific experiments, suggesting that he views fusion as scientifically impressive but unlikely to become the lowest-cost commercial energy source (which isn’t necessarily the true test for fusion energy).
In his analysis, Elon is right about a few things (everything else equal):
- From a build-time standpoint, nothing beats solar energy plus BESS. One gigawatt of solar/BESS takes 2-4 years to permit, develop, and build. By comparison, a 1GW natural gas plant takes 3-6 years to permit, develop, and build, while a 1GW nuclear power plant takes 10-15 years.
- Solar (and other renewable energy sources) is “greener” than any other power source on the planet, including fusion energy or nuclear fission. With that said, almost nothing is “truly green”, as even hydroelectric power requires significant amounts of concrete to build the dams, water sluices, and other infrastructure.
- Commercial fusion energy has a significant number of technical and schedule risks/unknowns to be solved, such as materials durability, tritium breeding and fuel supply, component replacement, construction cost, and regulatory requirements (these are expected to be resolved within the next 10 years).
Now for the part of the discussion where we diverge with Elon:
- The biggest challenges with solar energy includes that only some of the US is good for solar energy generation, the amount of land solar energy generation requires, and it needs high-voltage transmission lines from the generation site to the urban areas where the customers are located. A number of sources estimate that the amount of land required per GW of solar in areas highly favorable to solar tends to be between 5,000 and 10,000 acres (8 to 16 square miles), with the amount of land required being inversely proportional to the favorability of that land for solar energy production (less favorable equals more land).
- Overshadowing the actual land cost (which is typically leased at a cost of $500-$2,000/acre/year) is the actual cost for transmission lines if there are not ones that are close to the project and/or do not have extra capacity. With a typical site distance of 20 to 50 miles from an urban center, the cost of the transmission lines can reach close to a billion dollars, assuming that there are even utility corridors to run the lines.
While these costs do not make a solar energy solution “dead on arrival”, they can significantly extend the permitting times compared to a “brownfield” (existing site) conversion of a non-renewable power plant to energy sources such as fusion energy, nuclear fission or natural gas, making the solar solution less advantaged. And it doesn’t make areas with low solar production more desirable, an issue that Elon Musk did not address, which is why the EIA’s Annual Energy Outlook forecast puts solar at roughly 20% of US generation by 2050 – an important amount, but only part of the total electricity that the US needs.
The Use Case for Fusion Energy: Greenfield Vs. Brownfield
The US Department of Energy (DoE) describes fusion as having the potential to deliver abundant, reliable, zero-carbon primary energy, while ITER identifies grid and industrial baseload power as a central application. The “official“ primary use case for commercial fusion energy is to provide large amounts of reliable, zero-carbon electricity alongside variable sources such as wind and solar power. In the “official” use case, fusion energy can therefore serve as a baseload power source for regions that need dependable generation but have limited access to hydroelectric resources or suitable sites for conventional nuclear plants.
The larger concern limiting fusion energy’s use case in brownfield applications, is its commercial risk and schedule. Given the number of old electrical plants being retired, a brownfield utility site such as a coal plant or old nuclear fission facility would have valuable grid access and local workforce advantages. It is also likely that brownfield applications would roughly double the number of applications or opportunities for commercial fusion energy power plants. However for many utility companies, fusion remains an unproven emerging technology with a number of unresolved questions, making it critical that early applications of fusion energy deliver the answers required: costs, material survivability and overall schedule risk mitigation.
It Isn’t Solar vs Fusion; It’s How Quick Fusion Can Get To The Finish
In the US markets, commercial fusion energy’s greatest enemies are essentially geography and time for a number of important reasons:
- Baseline electricity in the United States is very cheap, with an average price of $0.18/kWh, vs $0.38-$0.43 per kWh in Germany. Even within the United States, prices vary significantly by state, with places like California and Hawaii having prices similar to those of Western Europe.
- Over the next 10 years, the cost of solar cells and battery energy storage system (BESS) technologies will drop significantly. At the same time, the efficiency of solar cells has increased from roughly 15%-17% a decade ago to 20%-22% today. These cost and technology advances make solar energy even more cost-advantaged vs commercial fusion energy.
- Massive overhauls are occurring in US electrical transmission systems over the next decade, increasing both capacity and reliability. This eliminates or significantly reduces one of the major hurdles to renewables in general, and solar energy in particular.
- Next-generation nuclear fission reactors like Small Modular Reactors (SMRs) are currently receiving far more near-term commercial interest and real-world utility partnerships than commercial nuclear fusion is, primarily due to nuclear fission’s technical maturity advantages, known regulatory pathways, and the Trump administration’s support for fission energy over the potential of fusion energy.
While these factors do not mean a “death knell” for commercial fusion energy, they likely mean that its ability to be taken seriously as a true mass-market energy resource in the US over the next decade is going to be challenging until the technological and economic hurdles for commercial fusion energy have been successfully overcome; effectively Elon Musk has not been proven wrong yet 😊. Let’s hope at least a few companies within the fusion industry have a chance to do so.
