MCE-5 VCRi: Pushing back the fuel consumption reduction limits

VCR is not on the carmaker’s roadmap

If fuel consumption reduction is on the strategic roadmap of carmakers then VCR should be on its technological roadmap. Yet, all carmakers don’t share this point of view and some have not put VCR on their roadmap. Some carmakers still consider VCR as an “ultimate” and technologically heavy solution and they are pushing it off to a future date when all the other solutions have reached the limit of their capabilities.

European objectives and penalties concerning
CO2 emissions make the “ultimate” grams of
CO2/km obtainable via VCR strategic ones

Most carmakers have evaluated or are currently
evaluating the potential of VCR to reduce
FC and associated CO2 emissions

The European Automobile Manufacturers Association
considers VCR as a credible way to reduce
automobile CO2 emissions

This strategy is hard to defend given the time required to develop a new technology: the rapid change in environmental and energy constraints will create increasingly large distortions between needs and available technologies. The “ultimate” grams of CO2/km obtainable via VCR will be cruelly lacking when the objective of 95 g CO2/km is in effect and used as a basis to calculate fiscal and regulatory penalties. Years of “VCR” profitability will be irreparably lost to the detriment of car owners, civil society and the carmakers themselves.

It’s difficult to lay any blame for this. The VCR question remains essentially linked to the availability of a technological solution capable of meeting the very stringent specifications of this type of engine. There is no doubt that if a “miracle” solution existed to control the compression ratio without challenging current engine definitions and the investments made to produce them, VCR would already be on the market.

For this reason, many carmakers have put VCR on their “in principle” roadmap but not on their effective one. VCR is on their minds but past experiences in this field were not technologically or energetically encouraging. Those who suffered disappointments with VCR engine prototypes tend to think that it will never happen. Others who have never started to work on VCR want above all to validate or invalidate in-house technological solutions, often based on not very promising principles. Furthermore, gains have mostly been largely underestimated since they were measured with insufficiently efficient technologies. The perceived lack of urgency to produce VCR engines is the direct inheritance of these evaluations.

VCR will only finally find its place on carmakers’ roadmaps when the energy and functional results obtained reach the objectives. The technology that reaches these results will then be recognized and adopted, providing it is the sought after technico-economic compromise. MCE 5 VCRi technology has delivered those results and has already brought them beyond the most ambitious objectives. It must now be sufficiently recognized to be adopted. When that happens, VCR will naturally take its place on the engine development roadmap drawn up by all carmakers.