Fraunhofer Analysis Finds Many European PHEVs Burn Far More Fuel Than Type-Approval Suggests
Key findings and regulatory stakes from the Fraunhofer PHEV analysis
A new joint study by Fraunhofer ISI and the Öko Institute examined real-world behavior in plug-in hybrid electric vehicles across Europe and surfaced a large gap between lab-approved consumption and on-road fuel use. The researchers analysed on-board monitoring streams from roughly 1,000,000 PHEVs and found average measured consumption clustering near 6 L/100 km, a multiple of the values used in type-approval calculations.
Performance varied widely by make and model: several mainstream, lower-cost PHEVs recorded measured consumption under 1 L/100 km, while high-performance variants — notably a Porsche model in the sample — registered around 7 L/100 km. The authors stress that the conventional regulatory metric, the utility factor, and how it is applied materially shapes reported fleet emissions and compliance outcomes for manufacturers.
Industry trade groups have defended existing measurement procedures as consistent with EU rules, while Fraunhofer advocates deploying real-world OBFCM datasets to align approval numbers with operational patterns. The report connects vehicle design choices, driver behavior and company-car deployment practices to the gap, arguing that market incentives and reimbursement structures often discourage regular charging. Policymakers now face a choice: tighten testing and accounting, or preserve the status quo that currently cushions manufacturer compliance numbers.
Read Our Expert Analysis
Create an account or login for free to unlock our expert analysis and key takeaways for this development.
By continuing, you agree to receive marketing communications and our weekly newsletter. You can opt-out at any time.
Recommended for you
European EV Demand Outpaces Expectations as BMW and Mercedes Scale Production
New order surges for BMW’s iX3 and Mercedes’ all-electric GLC have forced both manufacturers to expand manufacturing shifts and push production timelines forward. European sales data show battery-electric vehicles overtook petrol in December 2025 and posted double-digit growth year-over-year, signaling accelerating market momentum.
EPA vehicle-rule rollbacks create net cost to Americans, agency analysis shows
The EPA’s regulatory rollbacks on light-vehicle greenhouse-gas standards produce a net economic loss according to the agency’s own impact study; the agency has also submitted a related proposal to OMB to rescind the 2009 endangerment finding, deepening legal uncertainty. EPA tables show about $1.1 trillion in upfront vehicle price reductions versus roughly $1.5 trillion in higher fuel and ancillary costs through 2055.
Energy Department Removes EV credit tied to 'fuel content factor'
The U.S. Energy Department said it will remove the calculation known as the fuel content factor , which had given electric vehicles added weight in regulatory fuel-efficiency accounting. The move, prompted by a federal appeals court ruling, comes as part of a wider reworking of vehicle efficiency rules and could shift the balance of incentives toward market and state-level measures.
Trump Administration Repeals EPA Endangerment Finding, Steering U.S. Auto Market Toward Trucks and Hybrids
Removal of the EPA endangerment finding (now in OMB review) plus Congress’s elimination of CAFE penalties and parallel agency accounting changes (DOE’s fuel‑content factor removal) erode the federal compliance floor that supported large-scale EV economics. Automakers face clearer near‑term commercial incentives to favour higher‑margin trucks, SUVs and smaller‑battery hybrids even as the EPA’s own regulatory-impact tables flag larger lifetime fuel and health costs—creating legal, market and international frictions over the next 6–12 months.
Which automakers electrified fastest in the US in 2025?
In 2025, U.S. electrification progress was led by premium nameplates and several consolidated OEM groups — Cadillac, Audi and Porsche posted the highest BEV shares — while mainstream volume brands remained in the mid-single digits. Global competitive pressures (notably lower-cost, high-volume Chinese entrants), regional patterns showing availability and price trumping policy signals, and gaps in charging and used-vehicle markets all helped shape demand timing and point to where automakers and policymakers must focus to broaden adoption.
Report: Managed EV Charging Can Significantly Expand Distribution Capacity and Cut Costs
A Brattle-analysed modelling study and accompanying field trial for EnergyHub show that centrally coordinated EV charging can sharply reduce coincident demand and materially increase local hosting capacity, enabling utilities to serve many more vehicles on the same infrastructure while deferring upgrades. Commercial aggregation platforms and bidirectional-capable deployments are starting to bridge this technical capability to real-world procurement and monetization, but interoperability, customer availability, and regulatory compensation will determine realized value.
California Posts New ZEV Sales Milestone as Satellite Data Links EV Uptake to Lower NO₂
California recorded 79,066 new zero-emission vehicle registrations in Q4 2025 and exceeded 2.5 million cumulative ZEV sales, despite waning federal incentives. A neighborhood-level satellite analysis ties rising ZEV adoption to measurable reductions in nitrogen dioxide, while market data show Tesla losing ground amid growing hybrid demand and legacy automaker moves into BEVs.
Europe’s Commission quietly shifts: electricity treated as infrastructure, not a tax base
A leaked European Commission recommendation urges Member States to cut VAT and excise on electricity, remove levies from bills, and align retail taxation to favor electrification. The change reframes electricity as a critical economic input rather than a heavily taxed consumer commodity, but the proposal stops short of mandatory fossil fuel tax rises or binding timelines.