The 2026 Formula 1 power unit regulations will give an important change to the engine front, not only in terms of the technical content of the engines, but also the regulatory approach by the union. Indeed, in current engines, the power of the combustion unit is limited by a dual flowmeter, which measures that the instantaneous flow rate in the mass of fuel is less than the specified maximum At 100 kg/hr from 10500 rpm and above. From 2026, on the other hand, thanks to the advent of new fuels, the maximum mass flow rate will be replaced by the energy flow limit.
Indeed, in order to encourage research, the following Technical Regulations provide for broad freedom in the methodologies and sources of fuel production, consisting of a mixture of bio-components and synthetic gasoline. Thus preventing the use of gasoline with different energy content, between 38 and 41 MJ/kg, The Federation will not impose a limit on the overall fuel flow rate, but for an energy flow that cannot exceed 3000 MJ/hr. As said on the pages FormulaPassion.it Written by Claudio Lombardi, former director of Maranello’s engines division, this is an approach that has revitalized discussions in the circuit fifty years ago: “Personally I have always been an advocate, of this regulation created in 2014, of the flowmeter in relation to the development of the internal combustion engine, because it is the right concept. The instantaneous flowmeter is provided, of which a maximum value is charged, and if the engineer is skilled and efficient it can release energy more than others. It’s a point we already talked about in the 70’s: In 1977/1978 I wasn’t in Formula 1, I was still working in Lancia, but I went to watch the Grand Prix and being on your lap I was able to get into the pits, also considering that there are no restrictions now. While I met Keith Duckworth, the legendary designer of Cosworth, with whom we discussed what the ideal organization is. Duckworth came up with this concept that amazed me which I added to measure not only the instantaneous flow rate of gasoline, but the heat and power, so that it is open to any fuel.”
A similar approach was introduced on current hybrid power units, for which there is a limit on the mass flow rate of the fuel. As Lombardi emphasized, the need for engine engineers to increase efficiency to get the most out of the given fuel has led to tangible technological advances: “Having been suggested several times, it has not been implemented for various reasons. So I really liked that it was introduced as a concept in the 2026 regulation and in fact in the last period it gave advantages. The last aspirated Ferrari I worked on, the 12, had an internal combustion engine efficiency of between 30 and 32%, plus the last aspirated eight that I got some data from later. With these actuators, it is proven that up to 50% efficiency can be reached. It is the first time that it can be said without hypocrisy that racing engines have had an impact on research into chain production and on the knowledge of manufacturers.”
The approach will be revised in 2026, so as to effectively address some of the loopholes in the current regulations. In fact, in 2015, Enrico Benzing was already writing on the pages FormulaPassion.it How the mass flow rate control did not take into account density and convert the flow itself to volume, leaving room for inconsistencies among engineers in the power actually entering the engine: “The rule that I consider the most deplorable today, is – already much discussed – regarding fuel. I do not find it “correct” to impose a quantity of fuel based on weight (100 kg in GP), with a capacity of 100 kg/hr, measured in liters by a mass flowmeter and translated into kilograms, without declaring the value of the specific weight of the gasoline used. This means that at any time the indicators can be changed from liters to kilograms … Why is this value kept secret?Hence, from 2026, the energy flow entering the engine will be directly regulated, as the FIA measures the mass flow rate and performs the conversion using the fuel energy density values measured by the samples provided by the teams. By limiting the energy flow, it will work The union is on instantaneous power, but Formula 1 is considering whether to introduce an additional benchmark on the total power that can be used in the race, which in this case would also interfere with average power.