Much has been made of the incredible efficiency of the current generation of hybrid power units used in Formula 1. There has been some discussion in the comments of some of the recent articles here about how the efficiency figure was calculated. Simplistically, this is just the maximum power delivered by the power unit divided by the maximum power available from the fuel used.
The technical regulations specify the fuel that is to be used:
19.1.1 The purpose of this Article is to ensure that the fuel used in Formula One is petrol as this term is generally understood.
19.1.2 The detailed requirements of this Article are intended to ensure the use of fuels that are composed of compounds normally found in commercial fuels and to prohibit the use of specific power-boosting chemical compounds.
While the regulations do not specify the maximum energy contained within the fuel, and I am sure that the individual fuel and lubricant suppliers will be working hard to formulate fuels that deliver that little bit extra performance, we can make an estimate based on the energy within the commercially available fuel that we put in our cars. An internet search gives a range of values, these range from 36.4 – 49.6 MJ/kg of gasoline. I am making an assumption that the fuel used in F1 will be at the top of this range (although this figure was for aviation fuel, which has an energy density greater than the fuels used for road vehicles).
The maximum flow rate of the fuel is limited by the regulations to 100 kg/hour, that is 0.027778 kg/second. Multiplying this rate by the energy density gives the maximum power within the fuel as 1,377,778 Watts. With 745.6999 Watts to a brake horsepower, that is 1847.63 bhp.
Mercedes has recently stated their intention of having 1000 bhp from their 2018 power unit, that would give them an efficiency of 54.12%. The same article states that Mercedes’ first hybrid power unit achieved an efficiency of 44%, that would equate to a power output of 813 bhp. A proportion of this maximum power is produced by the Motor Generator Unit – Kinetic (MGU-K), this is limited by the regulations to 120 kW (160.9 bhp). This is using the stored energy recovered from braking from the MGU-K or from the exhaust energy recovered from the MGU-H. Even during those portions of the lap when the stored energy is exhausted, the 2018 Mercedes will be producing 839 bhp, giving an efficiency of 45.41%, which is still 10% better than the 35% efficiency of the current non hybrid road cars.
With fossil fuels limited, the drive for efficiency will help the long term future of the sport. While many countries have long term plans to eliminate petrol and diesel engines from their roads, hopefully racing will continue in some form to use fossil fuels if only for historic classes. What do you think, is efficiency worth pursuing? Let me know in the comments.
Ow! The maths!
If F1 chooses to remain the pinnacle of technology& motorsport, I can foresee a future where the cars are able to harvest enough energy to reduce fossil fuel usage to minimal amounts.
A Grand Prix in 10 liters of fuel? 5 liters? 1 liter?
The way hybrid and other alt-fuels are advancing, reduction in fossil fuel usage is here to stay.
And what better way to stay road relevant (even though there isn’t really a need) than to reduce fossil fuel consumption.
Dead dinosaurs saved.
Less carbon emissions spewed.
Et al.
Yanno, with the phrase “commonly used fuel”, one could conceivably use a special mixture fuel and introduce it into the common market at the same time, thus circumventing the rule.
Paul, I don’t think that is possible with the way the regulations are worded. There are many more clauses in section 19 of the technical regulations that specify the make up of the fuel to be used.
NC, What does “invalid security token” mean?. That is what I got when I posted.
I’m working on a few of the niggles and Rapierman has been keeping me posted on issues that aren’t working quite right. The edit function is open for about 15 minutes after you post something. I got the “reply” function up and running. Let me know if there are other issues. the devil is always in the detail when rolling out a new website with new features. :)
Many thanks for your attention/response, really appreciate your efforts. Yes the “reply function” has been restored, but the “edit function” disappeared again. As I said, at least from this side it is not as easy as before to post, and there are some other things that needs attention, but a start is always a start and again your efforts and determination are greatly appreciated. Wishing you and all those at Parc Ferme as well as all those that follows as posters all the best and a happy new year.
Many countries have long term plans to eliminate petrol and diesel engines from their roads but hybrids are not in their plans to eliminate.
In 2016 it was declared that the PU has gained 109 BHP since 2014 and that it was approaching 1000 BHP at 50% efficiency. 1000 BHP minus 160 electrical HP means that the ICE was producing 840 BHP. it also means that in 2014 the ICE was producing 730 BHP when at 44% efficiency.
Fuel used in F1 have roughly 0.5% additives, and one will be amazed how big HP gains could be made with them.
Having had to post 4 times and short posts due to difficulties encountered when posting. This plus both reply and edit facilities does not function.
Try it now.
Yes the reply facility is working and thanks for your prompt attention.
The edit facility is missing fro on this page.
Thanks again, the edit function is now up and working. but still not as normal as before to post.
No. All this expensive research and development belongs in the laboratory and test track, not on the race track.
While the pursuit of efficiency is nice, I think we’ve reached the point of diminishing returns. Check back over the records and see how many teams have been able to stay under the limit as opposed to past years. If only a few can stay under, then can we say that it’s unfair because it “de-facto” favors one or just a small handful of team(s) over others?
The pursuit of efficiency is something to be commanded. As with everything that is pursued the gains will always tends to diminish. As with every formula raced under, there will be those that does a better job then others. But, I for one don’t see the system as unfair for those that didn’t do as good a job as some others did, or that the system favored those that did a good job.
https://m.youtube.com/watch?v=mjCRUvX2D0E
Slip this one in the next time you talk about horse power
Keep up the good podcasts
One cannot talk about efficiency without talking about horse power/fuel.
The USA alone has enough reserves of natural gas to last for 400 years.
However the worldwide oil reserves will only last forty years at the current rate of consumption.
Natural gas is not gasoline, but you knew that anyway.
Dave, “power unit efficiency” a truly stupendous way to start not only the new TPF but also the New Year, disappointed with the lack of participation, everybody seems to be on holiday.
Technically speaking the claim of 50% efficiency does not include the permitted 161HP ERS power allowed to be added to the crankshaft, the 50% efficiency claimed is only horse power produced by the crankshaft.
Do you have a source where this is detailed?
Does that also claim the 1000 bhp for the PU excluding MGU-K, or are we talking 839 bhp?
When a competent technical engineer speaks about efficiency unless (and this with all due respect to all) one is technically inclined/up-to-date and better still technically competent, one is easily confused and prone to misinterpret what is being claimed by such competent technical engineers. Example is poster “subcritical71” on another page querying Andy Cowells claims on the efficiency reached by the present PU while claiming he is up to speed on such matters. Anyhow, The claims of “efficiency/s” reached: claims of the “PU” having reached an output of 1000HP and an efficiency of 50%. It means that the ICE part of… Read more »
840bhp at 50% efficiency means that the fuel has an energy density of only 45MJ/kg. That is lower than petrol that you can buy in most filling stations in the UK. That is why I asked if you had a link to the source of your information.
This here subject revolves around Andy Cowell claiming that the present power unit has reached an output of 1000BHP and that a 50% thermal efficiency has been reached. From his claim of the power unit BHP output we know what BHP output the “ICE” (part of the power unit) has reached. As regards his efficiency claims, he was technically talking about “thermal efficiency”, and as such no output from an outside source “ES” can be added to his calculations. What he was saying is that 50% of the potential that can be derived of a unit of petrol as that… Read more »
The ES isn’t external to the Power Unit, the energy stored within it has been recovered from both the kinetic energy of the vehicle and the “heat” energy in the exhaust. Both of these ultimately came from the energy within the fuel in the first place, so it is entirely valid to include this within the calculation.
I don’t believe that the fuel used in F1 will have a lower energy density than that available commercially. The 50% efficiency figure only makes sense if the output of the MGU-K is included.
The “ES” isn’t external to the “POWER UNIT” It is external to the “ICE”.
If one includes “ES” power to the “ICE” crankshaft produced power it will not be “ENERGY EFFICIENCY” but “OVERAL EFFICIENCY”.
The fuel used in F1 is supposed to have the same “ENERGY DENSITY” as the commercially premium unleaded pump fuel.
Edit: Nothing good can come of sliding to the level of a troll so I will delete my original post.
“Example is poster “subcritical71” on another page querying Andy Cowells claims on the efficiency reached by the present PU while claiming he is up to speed on such matters.”
For clarification, Salvu or Sunny or whatever you call yourself today, you have once again mis-represented facts and intentions of my posts. Its an alarming trend of yours, but in line with the typical tactics of a troll. That is all I will post on this topic.
What can I say? if one cannot stand the heat in the kitchen, its better to get out the kitchen then being un-civic to others that doesn’t agree.
My bad, needs a correction, I meant to say “being un-civil to others” that doesn’t agree by reverting to calling others trolls”
Eliminating carbon based fuels isn’t being done because they are running out, but because of the harm the byproducts are doing to the environment.
The evidence is sufficient to convince most of the worlds scuentists and decision makers,
https://climate.nasa.gov/evidence/
Happy New Year Dave, thanks for the really interesting article. It does seem that Mercedes, and the other p.u suppliers, are being a bit obscure with their claims around efficiency and power output. I’d always assumed the efficiency claims would have to relate to the peak output of the i.c.e / turbo / mgu-h, excluding any input from the energy store via the mgu-k, as that’s the maximum rate of converting input energy to output. But I guess ‘Greater than 50%’ sounds much more impressive than 45.41%. However as you note 45.41% is still 30% more efficient than most modern… Read more »
Overall efficiency is one thing and thermal efficiency is another, overall efficiency reached in F1 is much higher than the 50% thermal efficiency reached.
Yes there is technology transfer between F1 and road car engineering, example is “NANOSLIDE” technology used to coat cylinder bore surface. than there is indirect transfer, where F1 serves as a research laboratory for developing new solutions and showing the world what’s possible.
My calculations from what those that are directly involve said, so I call them my personal opinions and interpretations only.
Fuel used in formula 1 consists of the same components (compounds) that are found in commercial premium unleaded 98 RON.
At the permitted 100KG/H fuel flow rate there is a “POTENTIAL OUTPUT” OF 1240 kw of power.
“POWER UNIT” BHP output= 1000 BHP.
“POWER UNIT” BHP per litre= 625 BHP/L.
Overall “POWER UNIT” efficiency= 59%.
“ICE” BHP output= 840 BHP.
“ICE” BHP per litre= 525 BHP/L.
“ICE” THERMALL EFFICIENCY= 50%.
1240kW of power available from the fuel means that it has an energy density of only 44.64MJ/kg.
This is considerably less than commercially available 98RON fuel (46.7MJ/kg typically).
So either F1 fuel companies are using particularly poor fuels for racing, or your assumption that the MGU-K output is not included in the efficiency calculations is wrong.
Andy Cowell/Paddy Lowey Feb 2016: “The fuel has a potential output of 1240 KW at 100 KG/H fuel flow rate”.
The components used in commercial premium unleaded 98 RON must be the same as those used in the F1 fuel, the only difference is F1 does not specify octane rating for the fuel.
When technically talking “OVERALL EFFICIENCY” one is talking about the ES and ICE crankshaft combined power.
When technically one is talking “THERMAL EFFICIENCY” one is talking “ICE” crankshaft power only.
Although I already touched upon the mandated fuel used in F1 and the why and how of its effect on BHP produced, there seems the need to talk some more, or better say explain things a bit better, if for nothing, to eliminate most of the misconceptions/misunderstandings/ misinterpretations. All components that makes-up the composition of the commercial premium unleaded 98 RON must be the same in the F1 fuel, but the FIA does not speak of the octane rating in its mandated fuel. There are approx. 0.5 additives/components in the fuel composition that when differently configured can lead to huge… Read more »