The Numbers that Matter
- Dario Galli-Zugaro
- 7 hours ago
- 15 min read
The Greenest Car - why driving your classic might just be the most sustainable form of transportation, when using a sustainable fuel.
If you only read one thing, read this
Atmospheric CO₂ has risen from 315 ppm in 1958 to 432.5 ppm in 2026 - and the rate of increase is accelerating. This is the frame within which heritage motoring now operates.
Classic cars are climatically trivial in absolute terms - but that is not a licence to avoid responsibility. It is the starting point for an honest conversation.
The metric that matters is lifecycle carbon, not tailpipe emissions. A new electric SUV carries 12-17 tonnes of manufacturing carbon before it is driven a metre. Your classic's manufacturing carbon was emitted decades ago - it is already sunk.
The greenest car is, very often, the one already in your garage - especially when run on sustainable fuel, which cuts lifecycle emissions by 80-95% and is already proven at the limit in Formula 1, WRC and Le Mans.
The honest formula: keep driving, switch to sustainable fuel where you can, and retire the residual emissions through documented, independently verified carbon-removal projects.
Ready to act on the numbers? Net-Hero retires verified carbon-removal credits on your behalf and sends you a certificate of retirement. Learn how it works →
The longest continuous record of atmospheric carbon dioxide in the world comes from a single observatory on the slope of a volcano in Hawaii. Since March 1958, when David Keeling set up his first sampling equipment at the Mauna Loa Observatory, the measurement has run unbroken, paralleled since 1974 by independent data from the National Oceanic and Atmospheric Administration, and it has become the baseline against which every other climate claim is measured. It is, in the truest sense, the number that matters.
The data itself is stark. In 1958, atmospheric CO₂ stood at approximately 315 parts per million. By June 2026, it had risen to roughly 432.5 ppm. Not a doubling, not yet, but a rise of 117 ppm in sixty-eight years, and the rate of increase has itself accelerated. Where we once gained three ppm per decade, we now gain roughly two ppm per year. The seasonal variation, the annual dip and recovery as the Northern Hemisphere's growing season absorbs carbon and then releases it again, remains as reliable as clockwork. But the baseline around which that oscillation occurs keeps rising, and it shows no sign of slowing.
This matters to the heritage motoring community for a reason that has nothing to do with guilt and everything to do with credibility. It also matters because the answer is not what most people assume.
What the Mauna Loa record actually tells us
Atmospheric CO₂ has become the shorthand for climate concern, but the number itself is abstract. What matters more is what it does. Rising atmospheric concentrations drive warming, and warming drives consequences that are no longer hypothetical. They are measurable, they are accelerating, and they have begun to reshape the world in ways that affect every sector, including ours.
The mechanism is straightforward. CO₂ is a greenhouse gas, it absorbs and re-emits long-wave radiation, preventing heat from escaping the atmosphere. A rise from 315 ppm to 432.5 ppm represents a 37% increase in radiative forcing. The atmosphere is now trapping significantly more heat than it was in 1958. That heat has to go somewhere, and it goes into the climate system: the oceans warm, ice melts, atmospheric energy increases, and the hydrological cycle intensifies.
The consequences are not uniform. They are hardest on the sectors & people least equipped to manage them. Agricultural productivity is flattening in some of the world's most productive regions, such as the American Midwest, the Indian subcontinent, and parts of the North China Plain, as heat stress and drought stress collide. The 2012 US drought cost roughly $35 billion in crop losses and triggered a global spike in commodity prices that rippled through food security in lower-income countries. The 2023 North African and Middle Eastern heatwaves pushed temperatures to levels that made outdoor work physiologically unsafe. Extreme weather, wildfire, flood, and severe convection are increasing in frequency and intensity. The insurance industry is responding by withdrawing from high-risk jurisdictions and repricing risk upward across the board.
For wealthy countries with sophisticated infrastructure, these effects are manageable, though expensive. For the global poor, subsistence farmers in sub-Saharan Africa, coastal communities like the ones in Bangladesh, small-island states, they are becoming existential. The humanitarian cost is real, it is growing, and it is documented. The atmospheric CO₂ measured at Mauna Loa is the line connecting those consequences back to their root cause.
This is not activist rhetoric, rather the conclusion of every major scientific assessment from the Intergovernmental Panel on Climate Change, the US National Academy of Sciences, the UK Committee on Climate Change, and the European Environment Agency. It is also increasingly the conclusion of the insurance industry, the agricultural sector, and the geopolitical risk analysts in government and business.
It is, in other words, the frame within which the heritage motoring community now operates. We cannot wish it away. We can, however, think clearly about what responsibility actually means within it.
The uncomfortable truth about classic cars
Here is where most conversations in the heritage space go wrong. It is easy, and seductive, for those of us who own and drive classic vehicles to observe (correctly) that we are climatically trivial in absolute terms. Transport accounts for roughly 27 per cent of global emissions; historic vehicles are a rounding error within that figure. A Jaguar XJ6 out for a Sunday drive through the countryside is not the driver of the Mauna Loa trend.
But that argument has become a kind of trap. The uncomfortable observation that other bodies in this space avoid is that correctness at the global scale does not translate into permission to think carelessly at the personal or organisational scale. When you are standing in front of an audience that understands the Mauna Loa record, that knows what 432.5 ppm means for agricultural systems and insurance markets and coastal cities, the "we are trivial so we need not think seriously" position does not survive scrutiny.
Net-Hero's position on this is explicit: classic cars are climatically trivial in absolute terms. That is not a licence to avoid responsibility. It is the starting point for an honest conversation about what responsibility actually means.
The honest measure: lifecycle carbon Most public conversation about vehicle emissions has been framed in a single, misleading metric, tailpipe carbon, or what engineers call tank-to-wheel emissions. This makes the comparison feel simple and makes battery-electric vehicles look like the unambiguous solution. The truth is more interesting and more useful. The metric that matters is lifecycle carbon, well-to-wheel, or WtW, which counts every gram of CO₂ emitted from the source of the energy, through production and distribution, all the way to the tailpipe. It includes the carbon cost of manufacturing the vehicle itself, a cost that is large and often invisible. It also must include the disposal of the vehicle (cradle to grave). Producing a typical new car emits several tonnes of CO₂ before it is driven a metre. For a battery-electric vehicle, the figure is meaningfully higher than for a comparable petrol car, because of the battery. The cell-level embedded carbon ranges from 60 to 120 kilograms of CO₂ per kilowatt-hour of capacity, depending on chemistry and manufacturing location. A seventy-kilowatt-hour pack, typical for a mid-range BEV (battery electric vehicle), therefore carries four to nine tonnes of embedded carbon before the first kilometre is driven. That manufacturing carbon has to be paid back through lower running emissions. On a clean grid, the payback is relatively fast, perhaps 25,000 to 40,000 kilometres. On a dirtier grid, it takes considerably longer. A new electric vehicle charged primarily on coal-fired electricity has a meaningfully different lifecycle profile from one charged on a renewables-heavy grid. Now consider the alternative: the classic car in your garage. The 1965 Aston Martin DB6, the 1972 E-Type, the 1970 Rolls-Royce Silver Shadow. The embedded carbon of that vehicle was emitted in the year it was manufactured. It is not emitted again. The question is not whether to incur that manufacturing cost; that cost is already sunk, already in the atmosphere, already part of the historical record. What you can control is the running emissions. If you drive a beautifully maintained 1965 grand tourer for 1,200 miles per year, the average for a UK historic vehicle, according to the Federation of British Historic Vehicle Clubs, you produce roughly four to five tonnes of CO₂ annually on petrol or diesel. If you switch to a sustainable fuel with a lifecycle carbon saving of 85 to 95 per cent versus fossil fuels, you reduce that to 0.2 to 0.75 tonnes. The residual emissions can be retired through documented, independently verified carbon-removal projects. Compare this to the alternative: retire the classic vehicle and replace it with a new electric SUV. The manufacturing carbon bill is immediate and substantial, seven to nine tonnes for the battery alone, plus another five to eight tonnes for the rest of the vehicle. That is 12 to 17 tonnes of CO₂ released into the atmosphere today, in 2026, when our atmospheric carbon budget is most stressed. The BEV will eventually recover that manufacturing debt through lower running emissions. But the timeline depends entirely on how much the vehicle is driven. A vehicle driven 15,000 kilometres per year, typical for an everyday car, recovers its manufacturing carbon in three to five years. A vehicle driven 1,200 kilometres per year takes 30 to 40 years. This is the insight that the Kyushu University study made explicit: if Japanese car owners simply extended their vehicles' lives by ten per cent on average, the country's total automotive carbon footprint would fall by 30.7 million tonnes, equivalent to a one per cent reduction in Japan's entire national CO₂ output. Asset retention is climate policy. The greenest car is, very often, the one already in your garage. The corollary is less comfortable. If you own a classic vehicle and you drive it regularly, you accept a responsibility: the responsibility to use the cleanest fuel available and to offset the residual emissions through documented carbon-removal projects. Not as a guilt gesture nor as a marketing claim, but as an honest acknowledgement of the atmospheric impact caused by our tail pipe emissions. Want to know your classic's real footprint? Net-Hero can help you calculate, reduce and retire the emissions of your classic — with independently verified carbon-removal credits and a certificate to prove it. Get started →
Want to know your classic's real footprint? Net-Hero can help you calculate, reduce and retire the emissions of your classic - with independently verified carbon-removal credits and a certificate to prove it. Get started →
The fuel that changes the equation
This is where sustainable liquid fuels enter the conversation, not as an ideal solution, but as a pragmatic one. Sustainable fuels, contrary to fossil fuels, are made using CO2 already existing in the atmosphere, and not introducing new CO2 into the system.
Sustainable fuels come in several families, each with distinct feedstock sources and lifecycle credentials. Understanding the difference matters because they are not all the same, and some supply chains are more credible than others.
Advanced biofuels, particularly HVO (Hydrotreated Vegetable Oil), are made from feedstocks that do not compete with food, used cooking oil, animal tallow, agricultural and forestry residues. HVO is already commercially available for diesel engines and delivers lifecycle carbon savings of 80 to 90 per cent versus fossil diesel. It is a drop-in fuel, compatible with existing engines, and is being deployed at scale by fleet operators and logistics companies across Northern Europe.
Sustainable Aviation Fuel (SAF), made using the HEFA pathway (Hydroprocessed Esters and Fatty Acids) from the same feedstocks, is what most airlines are flying today. The aviation industry adopted it out of necessity, no battery technology on the horizon can power a long-haul aircraft and it works. Airbus and Boeing aircraft running 100 per cent SAF have logged hundreds of thousands of flight hours without measurable performance degradation.
E-fuels, or synthetic fuels, are made from green hydrogen and captured CO₂, converted via Fischer-Tropsch chemistry into petrol, diesel, or jet fuel that is chemically indistinguishable from the fossil version. The Porsche-backed HIF Global plant in Patagonia produced its first commercial e-petrol in 2022. Aramco, Synhelion, Norsk e-Fuel, INERATEC and Repsol all have pilot or early commercial projects in motion. The lifecycle carbon saving is 85 to 95 per cent, and potentially higher with carbon-negative production pathways using biogenic or direct-air-capture CO₂.
The honest case for sustainable fuels does not rest on them being cheap today or available everywhere. It rests on three things: credible technology maturity demonstrated in the most demanding environments, cost trajectories that align with clean-energy learning curves, and demand pull from sectors that genuinely cannot electrify.
Motorsport is the proving ground. Formula 1 completed its transition to 100 per cent sustainable fuel in 2026. The World Rally Championship has run 100 per cent fossil-free fuel since 2022. Le Mans and the World Endurance Championship have run 100 per cent sustainable fuel since 2022. MotoGP runs 40 per cent sustainable fuel today and has committed to 100 per cent by 2027. These are not demonstration events or PR exercises. These are the most demanding motorsport environments on the planet, run at the limit of performance, over thousands of kilometres, in all conditions. The technology question is settled. The WRC's P1 Fuels blend, the ACO's TotalEnergies Excellium Racing 100, and the F1 Aramco e-fuel have all proved that sustainable fuel does not ask engines to compromise.
The cost question is legitimate and deserves a clear answer. HVO currently carries a retail premium of roughly 10 to 20 per cent over conventional diesel in the UK in 2026. E-fuels are currently more expensive, at roughly €3 to €5 per litre at the production gate. But the cost trajectory is credible. Most sector projections put e-fuel production costs at €1.50 to €2.50 per litre by 2030, approaching economic parity with fossil petrol on a carbon-priced basis by the mid-2030s.
This trajectory follows the same curve as every clean-energy technology before it. Solar photovoltaic cost fell 90 per cent between 2010 and 2020. Lithium-ion battery cost fell from roughly $1,100 per kilowatt-hour in 2010 to under $140 in 2024. Both declines were driven by scale, manufacturing learning, and enabling cost reductions in components and infrastructure. Sustainable fuels are at an analogous moment now, with credible cost-learning curves and demand pull from aviation and shipping that will guarantee scale regardless of what happens in passenger cars.
That demand pull is decisive. Aviation needs sustainable fuel because there is no alternative. The EU's ReFuelEU mandate requires six per cent SAF in aviation fuel by 2030, rising to 70 per cent by 2050. The UK SAF mandate is 10 per cent by 2030. Shipping is moving in the same direction, with the International Maritime Organization's 2023 strategy targeting net-zero emissions around 2050 and intermediate checkpoints in 2030 and 2040. Agriculture and heavy haulage cannot electrify in any practical timeframe. Classic motoring is not the driver of sustainable-fuel development. We are a small downstream beneficiary of fuels being scaled for far larger industries.
Putting it together: the practical framework
What this means for a classic car owner is straightforward, though it requires actual diligence rather than good intentions.
First, keep driving. The lifecycle carbon argument is real. A beautifully preserved 1970 E-Type, driven 1,200 miles per year on sustainable fuel, has a lower lifecycle carbon footprint than one that is scrapped to enable its owner to buy a new battery-electric SUV and trigger a fresh 12-tonne manufacturing carbon bill. This is not activism. It is arithmetic.
Second, switch fuels where you can. HVO is increasingly available for diesel-engined classics through specialist suppliers and fleet operators. Sustainable petrol is available trackside through specialist rally organisers and from suppliers including Coryton, P1 Fuels, TotalEnergies Excellium Racing 100, and Aramco. The mass-market availability question is not yet fully resolved, you cannot yet rely on every forecourt stocking e-fuel, but the direction is clear and the event-based supply chain is already working. Modern sustainable fuel formulations are engineered to be ethanol-free or low-ethanol drop-ins specifically for the classic and motorsport market. Independent testing from Coryton, Zero Petroleum and others has confirmed drop-in viability across a wide range of vintage engines with no measurable performance or reliability penalty. HERO-ERA’s Rally for the Ages, now in its 4th edition, offered Coryton’s Sustain Classic in the first 2 editions with very positive feedback. Younger generations are more sensitive to the environmental impact of business and activities and often find themselves aligned and connect with environmentally conscious initiatives, making the use of sustainable fuels a bridge that an aging industry desperately needs.
Third, offset the rest. The honest position is a combination: run on the cleanest fuel available, maintain the vehicle you already own, and retire the residual emissions through verified carbon-removal projects rated by independent bodies such as the Verified Carbon Standard. This requires due diligence: identifying a project, checking the ratings, in most cases, personally visiting a project in remote areas of the world, and documenting the retirement (NET-HERO sends out certificates of the retired credits).
But it is the most reliable current path for the heritage community to demonstrate climate responsibility without relying on speculative carbon-market behaviour or on claims about fuel that will not survive the next fraud scandal. Unfortunately, some scandals have surfaced regarding the feed stock being used to make advanced biofuels. Mass balancing and other issues facing this nascent industry will be the subject of future blogs.
The infrastructure argument
There is a quieter case for sustainable liquid fuels that deserves attention. The UK has approximately 8,400 forecourts, around 600 fuel terminals and depots, six operational refineries, and an interconnected network of pipelines that took the better part of a century to build. Total UK petroleum stock holdings are equivalent to roughly two months of net imports, held against the IEA 90-day obligation. This is national resilience infrastructure.
Sustainable liquid fuels are deliberately engineered to be compatible with that infrastructure. They flow through the same pipes, sit in the same tanks, and dispense from the same pumps. There is no parallel network to build. There is no stranded asset to write off. There is no new permitting to negotiate. The cost of replicating that infrastructure from scratch would be measured in hundreds of billions of pounds and would take decades.
Liquid fuels are also stockpileable in a way that electricity is not. An electrified transport system has days or weeks of buffer in emergencies. A liquid-fuel system has months. The fuel-supply crises of September 2000 and September 2021 in the UK, and the broader fuel-security questions raised since Russia's 2022 invasion of Ukraine and the more recent geopolitical bottleneck in Hormuz, have reminded policymakers that resilience is back on the strategic agenda. A diversified energy carrier mix is more robust than a homogeneous one.
This is not an argument against electric infrastructure, for it is clearly necessary. It is an argument for the value of the existing liquid-fuel infrastructure, and for the economic sense of keeping it in service by running cleaner liquid through it rather than letting it strand.
The regulatory horizon
Policy is moving, sometimes erratically. The UK delayed the ban on new petrol and diesel car sales from 2030 to 2035 in September 2023. The current Labour administration is reviewing that date. The Zero Emission Vehicle Mandate is in force, requiring rising percentages of new-car sales to be zero-emission each year. Heritage vehicles are not directly affected by these provisions.
The important question is whether sustainable liquid fuels will eventually receive regulatory recognition. The EU's carve-out negotiated in March 2023 allowed new internal-combustion cars using only "CO₂-neutral fuels" to continue to be sold beyond 2035. The European Commission was tasked with defining the conditions; that proposal has been delayed but remains expected. The UK position is still to be clarified.
The honest statement is this: heritage motoring's long-term viability rests on three things. One is that sustainable fuel is available at credible price and credible volume, a question being answered by aviation and maritime demand. Two is that regulation explicitly recognises lifecycle-neutral liquid fuels alongside electrification, still a question being debated in Brussels and London. Three is that the cultural narrative around heritage vehicles is positive, that they are seen as part of the solution rather than as a problem to be exempted from the transition.
The sector has more control over the third than the first two, and that is where the energy should go. Every time a heritage enthusiast, a club leader, or an industry figure frames the conversation as "we need to be part of the sustainable-fuel transition, not exempted from it," the cultural ground shifts. Every time we lead with the technical argument rather than the emotional one, we strengthen the position. Every time we acknowledge what we do not know and what we are uncertain about, rather than overclaiming, we build credibility that will matter when, not if, the next fuel-industry fraud scandal breaks.
What the Mauna Loa Observatory is really telling us
The Mauna Loa measurement is not an instruction, but rather, information. It tells us that atmospheric CO₂ is rising, consistently and measurably, and that the rate of rise is accelerating. It tells us that the consequences of that rise, in agriculture, in insurance markets, in geopolitical stability, in human welfare, are becoming visible. It tells us that we have less time than we did five years ago. For the heritage motoring community, it also tells us that the old defences no longer work. "We are trivial in global terms" is true but insufficient. "We are a cultural good" is true but insufficient. "We are low-mileage" is true but insufficient. The Mauna Loa baseline demands better. The better case is this: the classic car in your garage, driven responsibly on sustainable fuel, with residual emissions retired through documented carbon-removal projects, is a legitimate and even climate-rational choice. Not because it is perfect. Not because it solves anything. But because it reflects a serious engagement with the actual numbers, the 432.5 ppm in the atmosphere, the 1.5 billion combustion vehicles already on the road, the sectors that cannot electrify, the infrastructure that took a century to build, the cost trajectories that are beginning to align. Heritage motoring will survive because it is becoming part of a larger industrial logic, not because it is pleading for an exception to it. That is the argument to make and the future to build toward. The greenest car is, very often, the one already in your garage. What you do next is up to you.
Thanks for your continued support,
Dario Galli-Zugaro
What you do next is up to you — here's where to start.
Retire your classic's residual emissions with verified carbon-removal credits, certificate included. Offset now →
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Keep reading - more from Net-Hero on sustainable fuels, carbon removal and the future of classic motoring. More blogs →