Innengine signs MoU with Renault's Horse for crankless engine

Innengine brings its crankless engine into Renault's orbit

Can a 35 kg internal combustion engine replace one weighing 160 kg? Granada-based Innengine says yes and has signed a memorandum of understanding with Horse, Renault's powertrain division, to explore low-emission propulsion production. This is not a manufacturing order but an exploration phase contingent on prototype performance. The company has operated from an industrial park for years, surviving near-bankruptcy while refining its concept.

The engine eliminates the crankshaft, connecting rods, and valves. According to the firm, this architecture delivers conventional engine performance at a fraction of the weight, cutting fuel consumption by roughly one-third. Its natural application is not driving wheels directly but charging batteries in range-extended electric vehicles. Universitat Politècnica de València will host prototype testing, a validation signal that industry reads as proof there is substance beyond marketing.

What is a crankless engine and why is it so light?

The key lies in removing components that have defined internal combustion engines for over a century. Without a crankshaft or connecting rods, reciprocating motion is converted differently, simplifying the block. On paper, this yields a compact, lightweight propulsor suitable for applications where every gram matters: light aviation, drones, and range-extender vehicles.

Interest from the model aircraft sector is telling. In radio-controlled flying, where extra grams ruin maneuvers, the company already has a waiting list, according to forum participants. It is a niche market, but serves as a crucial test bed to see if the technology holds up or fails under stress.

Valencia university backing vs. technical skepticism

A viral video antiestéticatures an engineer arguing the design's wavy crankshaft would fail. Other analyses point to unresolved thermal issues and poor heat management. Answers lie not in online forums but in the upcoming tests in Valencia.

The company has not published consumption or power figures in available materials, fueling suspicion. Demanding concrete data—fuel use at max RPM, roller and bearing durability, behavior under 75% continuous load—is not arbitrary; these are standard questions any engine buyer asks.

Precedents: Mazda MX-30 and other failed small engines

This is not the first attempt to fit a small, light thermal engine into an EV. The Mazda MX-30 E-REV used a rotary engine described as shoebox-sized, resulting in extremely high consumption. The BMW i3 REX carried a tiny emergency motor with a 9-liter tank, which some drivers abused on long trips until it burned out.

The lesson is uncomfortable: small size alone is insufficient. Engines must be efficient, durable, and cheap to maintain. In aviation, certification is also mandatory. Lycoming, Continental, and Rotax engines dominating light aircraft were designed in the 1970s and 80s and remain because certification takes years and money, and global maintenance networks exist.

Airbus, drones, and military business

Airbus's interest in drone applications is cited as a potential commercial path. For single-use drones, long-term reliability matters less than power-to-weight ratio, where the Granada engine has advantages. Competing on price with certified, decades-proven Rotax engines is another challenge.

Large corporations find it cheap to explore technologies they can later write off. If something works, they keep it. This asymmetry explains why a memorandum with Renault does not equal a firm order.

The bottleneck is manufacturing, not design

Prototyping differs vastly from mass production. Machining individual parts on a CNC mill is nothing like creating casting molds and producing full series. If similar parts do not exist commercially and everything is made in China, the industrial leap is enormous. This, more than engine physics, determines whether the project reaches roads or remains in a drawer.

Context is challenging. In Spain, bureaucracy and EU timelines add friction to industrial innovation. That a Granada company reached this stage—with a Renault agreement and university testing—exceeds most achievements. Whether the engine is disruptive or a bluff will be known when prototypes run. Meanwhile, investors who have waited years continue watching from the sidelines.