Inertia Enterprises, a fusion energy startup, has raised $450 million in a Series A funding round. The capital will help the company build the world’s most powerful laser and advance its fusion power technology.
The funding round was led by Bessemer Venture Partners. Other investors include GV (formerly Google Ventures), Modern Capital, Threshold Ventures, Long Journey Ventures, and others.
Inertia was founded in 2024. The company’s mission is to make fusion energy a practical and clean power source for the grid. It plans to use its new funds to build key parts of its fusion system and to scale components that are essential for commercial power plants.
Fusion energy has long been viewed as a potential source of abundant, clean power. Inertia’s recent funding round is one of the largest for any fusion startup. It reflects growing investor interest in bringing fusion out of the lab and into real-world use.
What Fusion Energy Is and How Inertia’s Approach Works
Fusion is the process that powers the sun. It happens when light elements such as hydrogen combine to form a heavier element. This process releases a large amount of energy. Fusion does not produce carbon emissions, and it generates much less long-lived radiation than fission nuclear power.
Inertia’s technology is based on a fusion method called inertial confinement fusion (ICF). ICF uses powerful lasers to compress tiny fuel pellets. When the pellets reach high temperature and pressure, fusion reactions occur.
The company plans to build a laser system called Thunderwall. This system is designed to deliver powerful beams at a rapid rate. The laser will fire repeated pulses into fuel targets, generating the conditions needed for fusion.
Inertia’s founders include leaders with experience in fusion science and large-scale research facilities. This includes scientists from the Lawrence Livermore National Laboratory’s National Ignition Facility (NIF). Their experiments showed fusion ignition, which produced more energy than they used on the target.
The company’s CEO and co-founder, Jeff Lawson, previously led Twilio, a technology company that grew into a major communications platform. He now leads Inertia’s effort to translate fusion science into clean energy technology. He said,
“Our plan is clear: build on proven science to develop the technology and supply chain required to deliver the world’s highest average power laser, the first fusion target assembly plant, and the first gigawatt, utility-scale fusion power plant to the grid. Inertia is building the team, partnerships, and capabilities to make this real within the next decade.”
Inside the $450M Bet on Commercial Fusion
The $450 million funding round is considered one of the largest for a fusion startup in its early phase. The money will support several major activities, including:
- Building Thunderwall, the powerful average-power laser system.
- Developing manufacturing lines for fusion fuel targets.
- Creating the first pilot plant and laying the groundwork for future commercial plants.
- Scaling supply chains for components like laser diodes and fuel pellets.
Investors say Inertia’s technology has the potential to reach commercial-scale fusion energy faster than other approaches. They cite the company’s focus on proven physics from earlier lab experiments.
Co-founder, Dr. Annie Kritcher, remarked,
“In just three years, we’ve gone from the first experiment to ever produce more fusion energy than was delivered to the target, to repeating that result many times and pushing the target gain higher. We’re now focused on translating physics we know works into a pathway toward commercial-scale fusion energy, and the real benefits it can deliver for people and the planet.”
From Lab Ignition to Grid Ambition: Inertia’s Fusion Roadmap
Inertia’s approach relies on key breakthroughs made at the NIF in Lawrence Livermore National Laboratory. In December 2022, researchers reported a major breakthrough. They conducted the first controlled fusion experiment that generated more energy than it received.
The NIF success provided proof of concept. It showed that inertial confinement fusion could technically produce net energy in a single experiment. Inertia’s team includes some of the scientists from that effort.
- Inertia’s long-term goal is to build a fusion power plant with 1.5 gigawatts (GW) of capacity. A plant of this size could supply electricity for about 1 million homes.
The next challenge is to make the fusion process repeatable and efficient enough to produce continuous power. Inertia plans to use advanced diode lasers. These lasers are expected to be about 10x more efficient than older technologies. The company believes this will significantly lower the cost of fusion energy production.
Fusion Joins the Clean Energy Investment Surge
Fusion energy investment has grown quickly in recent years. Both governments and private companies are putting large sums into the sector. It is now part of a broader clean energy funding trend that includes startups pursuing both fusion and fission technologies.
Private fusion funding has exploded over the past five years. Total investment reached $13.2 billion by the end of 2025. That amount is up 8x from 2020, when just 15 companies raised $400 million.
The US leads with 53% (~$7B) while China holds 34%. Active companies surged 400% from 15 to 77, reflecting broader investor diversification across ICF, tokamaks, and stellarators. Inertia’s $450M sits atop this record-breaking year.
Some other fusion startups that have attracted significant capital include:
- Commonwealth Fusion Systems, with roughly $2.86 billion raised to date.
- Helion Energy, with more than $1 billion in funding and commitments.
- Pacific Fusion, reported to have raised about $900 million.
- General Fusion, with about $357 million raised.
Private capital flows into fusion are increasing as the global demand for clean energy rises. Many countries are moving to reduce carbon emissions and to invest in technologies that can provide large amounts of clean power with minimal environmental impact.
In the United States, the Department of Energy (DOE) awarded $134 million for fusion research programs. These include the Fusion Innovative Research Engine (FIRE) and the INFUSE program. The DOE said it could invest up to $220 million over four years in the FIRE initiative. The goal is to link national labs, universities, and private firms to speed up fusion development.
The DOE has also partnered with companies such as Kyoto Fusioneering to test fusion fuel cycle systems at Oak Ridge National Laboratory. These efforts aim to prepare key technologies for future fusion plants.
Private capital is also rising, as shown in the chart.
Italian energy major Eni signed a more than $1 billion power purchase agreement (PPA) with Commonwealth Fusion Systems (CFS). The deal covers electricity from CFS’s planned 400-megawatt ARC fusion plant in Virginia. The plant is expected to connect to the grid in the early 2030s.
CFS has also signed a deal with Google for 200 megawatts of future fusion power. These agreements show that large energy buyers are planning for fusion in long-term clean energy strategies.
- READ MORE: Google Backs Fusion Energy: Signs 200MW Offtake Agreement with Commonwealth Fusion Systems
Governments and corporations now see fusion as a long-term clean energy option backed by serious funding and market commitments. That is because fusion energy does not emit carbon during power generation and uses fuel that is abundant in nature, such as isotopes of hydrogen. This makes it attractive as a long-term clean energy option alongside renewables such as wind and solar.
Could Fusion Become the Ultimate Baseload Power?
Inertia’s $450 million funding round is a landmark moment for the fusion industry. It shows that investors are willing to back ambitious clean energy technologies with long-term horizons.
Fusion has the potential to provide baseload clean power — power that is stable and available around the clock. This could complement intermittent renewables like solar and wind.
If commercial fusion is achieved, it could transform the global energy landscape. Countries could reduce dependence on fossil fuels. Power systems could become cleaner and more resilient.
However, fusion still needs major technological breakthroughs before it becomes a practical energy source. Inertia and other fusion companies are working to solve the remaining scientific, engineering, and supply chain challenges.
The next few years will be critical for measuring progress. Successful fusion commercialization could mark a turning point in the global effort to achieve deep decarbonization and sustainable energy systems.
The post Fusion Breakthrough: Google Venture-Backed Inertia Raises $450M to Build World’s Most Powerful Clean Energy Laser appeared first on Carbon Credits.
The accounting differences that decide whether your nature investment shows up in inventory, in BVCM, or nowhere at all.
The question reaches a procurement team about three weeks before the next sustainability committee meeting. Someone has read about insetting. Someone else has just signed off on an offset purchase. The CSO wants to know if the two are interchangeable. The answer is no, and the GHG Protocol Land Sector and Removals Standard is the reason why.
This article walks through what each term means at audit-grade specificity, what the standards actually say about how each gets counted, and how to decide which tool fits which target. The insetting vs offsetting question is one of the most-searched in corporate climate strategy, and one of the most poorly answered. By the end of this piece, you should be able to brief a committee on the difference without notes.
The two definitions, in plain English
Offsetting means buying carbon credits generated outside your value chain and retiring them against your residual emissions. The reduction happens somewhere else, financed by you, and the credit is the receipt.
Insetting means investing in emission reductions or removals inside your own value chain, typically with suppliers, where the reduction is directly linked to the products and services you buy. The reduction happens inside the boundary of your Scope 3 inventory, and the accounting treatment is fundamentally different.
The shorthand from the University of Oxford’s Nature-based Insetting Initiative is useful: insetting is what you do with the supply chain you have; offsetting is what you do with the supply chain you do not have.
What the GHG Protocol Land Sector Standard actually says
The GHG Protocol Land Sector and Removals Standard, finalised in 2024 after a multi-year pilot, sets the rules for how land-based emission reductions and removals enter corporate inventories. The Standard distinguishes between inventory accounting (Scope 1, 2, and 3) and project or intervention accounting (a separate methodology for crediting).
For insetting, the practical implication is that supplier-level interventions, when properly measured and attributed, can reduce your Scope 3 category 1 (purchased goods and services) emissions in your inventory. The reduction is not a credit retired against the inventory; it is a lower inventory number, period.
For offsetting, the credit is retired separately. It can be reported as a contribution toward a net-zero claim under the SBTi Beyond Value Chain Mitigation framework or as part of a VCMI Carbon Integrity claim, but it does not lower the inventory number.
A practical consequence: if your Science Based Target requires a 50% absolute reduction in Scope 3 emissions by 2030, insetting moves you toward the target. Offsetting does not. This single point of difference reshapes the procurement decision.
When insetting counts toward Scope 3 (and when it does not)
Insetting counts toward Scope 3 only when several conditions are met:
- The intervention must occur with an entity in your value chain.
- The emissions reduction or removal must be measured against a defensible baseline.
- The reduction must be attributed to your share of that supplier’s output, not double-counted with other buyers.
- It must follow the inventory accounting rules in the GHG Protocol Land Sector Standard, not the project accounting rules used to generate credits.
The most common failure mode is double counting. If your supplier sells the same reduction as a credit on the voluntary market and also reports it to you as a Scope 3 reduction, the math breaks. The Standard requires you to address this risk, typically by purchasing and retiring the supplier-issued credit as part of your inventory or by contractual provisions that prevent the supplier from selling the reduction twice.
When insetting does not count toward Scope 3: when the intervention sits with a supplier you do not buy from, when the baseline is not defensible, when the attribution is unclear, or when the documentation does not survive audit. Those cases default to Beyond Value Chain Mitigation, which is still useful but operates on a different ledger.
The procurement and supplier engagement question
Insetting is harder than offsetting. That is the unfashionable truth most buyers eventually confront. Offsetting is a transaction; insetting is a relationship.
To run an insetting program, you need supplier mapping precise enough to know which farms or facilities sit at which Scope 3 boundary. You need an engagement model that gets suppliers to participate, which usually requires multi-year commitments and shared economics. You need an MRV architecture that measures the right things and produces audit-ready documentation. And you need a contractual structure that prevents double counting and protects both sides.
The trade-off you receive in return is significant. Reductions count against your inventory rather than your residual. Supplier relationships deepen, which protects sourcing continuity. Yield and quality improvements often follow regenerative interventions, which reduces your input cost over time. And the regulatory file, under CSRD, CSDDD, EUDR, and the SBTi FLAG Guidance, is materially stronger.
Choosing the right tool for the right target
A practical decision rule. If your target is a science-based Scope 3 reduction and you operate in a FLAG sector or source FLAG commodities, insetting is the structurally correct tool. If your target is a net-zero claim that includes neutralising hard-to-abate residual emissions outside your value chain, BVCM via high-integrity offsets is the structurally correct tool. Most companies with material Scope 3 exposure need both, in different proportions, sequenced over time.
The sequencing matters. Insetting takes longer to stand up but produces a permanent reduction in the inventory. Offsetting can be transacted faster but does not change the inventory and now sits under tighter claim restrictions. Treat them as complementary tools with different jobs, not as substitutes. The Accountability Framework Initiative and the IUCN Global Standard for Nature-based Solutions both provide useful guardrails for the insetting side, with biodiversity, human rights, and benefit-sharing requirements that go beyond carbon math.
If you are mapping a Scope 3 reduction roadmap and need to scope which interventions count toward your inventory versus which sit in Beyond Value Chain Mitigation, the carbon and sustainability experts at Carbon Credit Capital can help you structure a nature-based supply chain investment program that fits your FLAG exposure, your target architecture, and your audit horizon. Schedule a consultation.
Net zero is often described as a balancing act: cut what you can, account for the rest, and reach zero on the ledger. That framing is useful, but it leaves something out. It treats every tonne of carbon as interchangeable and every route to zero as equally sound, while the science tells a more specific story.
Malawi has lost a striking share of its forests over the past three decades. Woodlands that once covered well over a third of the country now cover less than a quarter, and the pressure on what remains is increasing. Behind those figures sit two practical questions: what is driving the loss, and what reverses it?
-
Climate Change1 year ago
Guest post: Why China is still building new coal – and when it might stop
-
Greenhouse Gases1 year ago
Guest post: Why China is still building new coal – and when it might stop
-
Greenhouse Gases2 years ago嘉宾来稿：满足中国增长的用电需求 光伏加储能“比新建煤电更实惠”
-
Climate Change2 years ago嘉宾来稿：满足中国增长的用电需求 光伏加储能“比新建煤电更实惠”
-
Climate Change2 years ago
Bill Discounting Climate Change in Florida’s Energy Policy Awaits DeSantis’ Approval
-
Renewable Energy10 months agoSending Progressive Philanthropist George Soros to Prison?
-
Greenhouse Gases1 year ago
嘉宾来稿：探究火山喷发如何影响气候预测
-
Carbon Footprint2 years agoUS SEC’s Climate Disclosure Rules Spur Renewed Interest in Carbon Credits