MACA, a French startup based in southeast France, unveiled its Carcopter, a hydrogen-powered flying Formula-1 at CES 2021 last week. Founders Thierry de Boisvilliers, and Michael Krollak, both veterans from Airbus Helicopters, aim at creating a Formula 1-type competition for flying cars to accelerate innovation in the zero-emission VTOL (Vertical Take-Off and Landing) market while generating revenues from the racing business.
The idea to design a race VTOL vehicle came to former fighter pilot Thierry de Boisvilliers and former Airbus Helicopters executive Michael Krollak while working at Airbus, an aerospace and VTOL innovation leader.
"A NEW PAGE OF THE AERONAUTICAL HISTORY IS BEING WRITTEN TODAY, AND WE WANT TO BE PART OF IT, SAID DE BOISVILLIERS."During my conversation with the Carcopter designers, I learned that MACA is supported by CleanTech, a startup incubator dedicated to clean energy based in the Aix-en-Provence region (Arbois), near the French Riviera. MACA was part of the French Tech delegation at CES 2021.
As the consumer drone market shows, innovations fly a lot faster than regulations, and new technologies lead to new policies. When it comes to the aerospace industry, major public safety concerns tend to slow down the Federal Aviation Administration (FAA) approvals. The first commercial drone delivery approved by the FAA took place on July 17, 2015. Five years later, the UPS drone services, the first FAA-approved drone airline, are still minimal, and Amazon has recently obtained its FAA clearance for trial flights.
We need various avenues to accelerate the emerging flying vehicle sector if we hope to see a world like Blade Runner in our near future. Designing an F1-type race for high-performance VTOL vehicles looks like a brilliant idea for that purpose.
How Does the MACA Carcopter Work and When Will It Race?
MACA expects to fly its second prototype at about 246 km/h at the end of 2021 and launch the first race with the final product in 2023
The MACA team is designing a 5.5 m (18 feet) long prototype that will weigh less than 600 kg (1,322 lbs) and is expected to fly for the first time at the end of the year.
MACA built the previous prototype at a third of the final Carcopter’s size (about 2m long) to validate the concept and the device’s architecture by the French government’s aerospace lab ONERA (Office National d’Etudes et de Recherches Aérospatiales). According to ONERA’s assessment, the full-size Carcopter will reach a maximum speed of about 246 km/h.
Co-founder Thierry de Boisvilliers says that the second prototype could deliver 35 minutes of autonomy, but not at maximum speed. Both founders will pilot their new flying Formula 1 and expect to launch the first competition in 2023.
Editor’s note: prototype’s specifications may change over time as the design process is ongoing.
Six hydrogen-powered 35 kW electric motors and six rotors
The MACA Carcopter features hydrogen fuel cells generating electricity for six 35 kW electric motors that power six rotors. The rotors are grouped by pairs in three locations (see image). Each rotor of the same pair is stack on top of the other and spins in the opposite direction: three spin clockwise (CW) and the other three spin counterclockwise (CCW).
A flight controller similar to the ones used in multi-rotor drones
The pilot onboard the MACA machine triggers the input using a control stick. That’s similar to drones that receive inputs in their onboard FCs via remote controls operated by humans on the ground. The flight controller is critical to accurately control a multi-rotor aircraft’s behavior from the control inputs, whether the pilot is onboard or on the ground.
A carbon and linen airframe
To achieve a lightweight, the airframe is made of carbon. MACA’s founders would like to add linen to the final product to reduce the weight further and to limit the impact on the environment. “The automotive industry is increasingly using linen in car manufacturing,” said co-founder Thierry de Boisvilliers.
Why Choose Hydrogen Fuel Cell Over Electric Battery for a VTOL racing vehicle?
How does a Fuel Cell Electric Vehicle (FCEV) works?
A Fuel Cell Electric Vehicle (FCEV) uses electricity to power an electric motor. Contrary to Battery Electric Vehicles (BEVs), aka all-electric vehicles, it does not store the electrical energy in a battery pack but instead uses a fuel cell powered by hydrogen stored in a tank to produce its electricity. Most hydrogen-powered vehicles emit only water and heat and are classified as zero-emission – more information on how an FECV works here and on the graphic below.
Hydrogen Fuel Cell vs. Lithium-ion battery: higher energy density, better endurance, and better lifespan
In aircraft technology, weight is critical; that is why hydrogen fuel cell is the MACA founders’ preferred energy source for their FCE flying Formula 1.
Hydrogen delivers far superior energy density, better endurance, and better life span than lithium-ion batteries. Most importantly, fuel cells do not require rare earth elements.
Lithium-ion is widely used as an affordable solution for short distances in all-electric aircraft designs by the air mobility industry. Still, it is not light enough for VTOL vehicles flying long distances in peri-urban zones. According to a research article published by Wanyi Ng and Anubhav Datta in 2019 on ARC, “For any mission beyond 50 miles, fuel cells appear to be a compelling candidate [for eVTOL]”. An assessment shared by Urban Aeronautics founder Rafi Yoeli, who said that hydrogen is the only way to make flying cars viable.
In order to store the hydrogen gas in a tank, it needs to be compressed or supercooled to a liquid. Both solutions are not cheap and lose energy in the process. However, when it comes to Formula 1 racing, performance wins over saving money.
According to a recent article by Billy Wu, lithium-ion batteries produce about 250 Wh/Kg. On the other hand, hydrogen gas (H2) could achieve 33,000 Wh/kg depending on the specific technology. Another source points to a potential energy density of about 44,000 Wh/kg (Watt-hour per kilogram).
According to Aviation Today, “HyPoint, a venture-funded company in Menlo Park, has demonstrated an air-cooled fuel cell powertrain that delivers 1000 Watts per kilogram of specific power with an energy of 530 Wh/kg“. The Menlo Park startup achieves more than double the energy density of current lithium-ion batteries. Dedicated to air transportation, the next version of Hypoint’s hydrogen fuel cell technology is expected to reach 2,000 W/kg and 960 Wh/kg by 2022, with a market release in 2023. HyPoint signed a partnership deal with Urban Aeronautics for its hydrogen VTOL CityHawk craft.
Other battery technologies are under development, such as sodium-ion (Na-ion) or lithium-sulfur (Li-S). OXYS Energy expects to achieve 500 Wh/kg by the end of the year with its Li-S battery prototype for eVTOL."FUEL CELL TECHNOLOGY DELIVERS ROUGHLY AS MUCH POWER WITH A FULL 40 KG HYDROGEN TANK AS A 150 TO 200 KG LITHIUM-ION BATTERY PACK – THAT IS A ROUGH APPROXIMATION, AND IT CAN VARY DEPENDING ON THE SPECIFIC TECHNOLOGIES, SAID CO-FOUNDER MICHAEL KROLLAK."
The MACA team would neither mention specific technologies nor describe more Carcopter’s technical specifications. Winning a motorsport race is all about designing the best machine for the best pilot, and racing teams cannot reveal their secret sauce.
Hydrogen tank vs. charging station: faster refueling time
Quick refueling time is another crucial advantage of Fuel Cell. It takes minutes to fill a hydrogen tank, while fully electric vehicles require 30 minutes to several hours for a full charge (depending on the charging station and battery capacity). We can imagine that flying race cars would have several fully charged lithium-ion battery packs ready for the swap during a competition. The question is which process would take longer, fueling a hydrogen tank or swapping a battery?
Flying F1 race: which competitors could race the MACA Carcopter in 2023?
The French startup’s ultimate goal is to launch a unique flying car race with “made in MACA” rules. MACA’s roadmap indicates that the Carcopter will be ready to race by 2023, but against which teams?
MACA founders envision a race with five or more MACA Carcopters, or competing against the current companies developing electric Formula 1 for the skies, such as Australian startup Alauda Aeronautics and its beautiful Airspeeder, or the Big Drone by DCL.
The French startup is currently looking for additional investments, or they could sell a few of its flying vehicles to wealthy motorsports aficionados, starting at €500K a unit (or more) – they already received a call from a potential buyer.
Why are lithium batteries the current preferred energy storage medium over hydrogen for electric cars?
Despite its higher energy density, long-range (~300 miles in 2020), and fast refueling time, hydrogen (H2) for cars is not widely available in the United States compared to lithium-ion. The reason: the hydrogen storage and delivery infrastructure cost much more than the charging stations connected to the grid. The lack of infrastructure makes an FCEV four to eight times more costly per kilometer than a BEV, according to investment firm Triple Point.
Today in America, hydrogen as an energy source for commercial cars is mostly used in California, where manufacturers test the technology’s market viability. The U.S. government is looking at solutions to tackle the hydrogen storage challenges. Researchers study the path to low-cost hydrogen transportation via liquid hydrogen, and they expect ~$4.3 to $8 per kilometer around 2030. Despite the difficulties, the hydrogen infrastructure is increasing worldwide.
Since 2010, the cost of a lithium-ion battery per kWh has dropped by almost 90%, from $1,183 in 2010 to just $156 in 2019. The infrastructure and electricity production costs are not included in this calculation.
Lithium-ion vs. hydrogen: a heated debate among car manufacturers
The heated debate is still ongoing among car manufacturers, Toyota and Honda are betting on hydrogen, while Tesla and Volkswagen favor all-electric vehicles. BMW and Hyundai are developing both solutions in parallel.
In a recent article, citing a study by Horváth & Partners, Volkswagen explains why batteries and not fuel cells are better for cars. According to the German automaker, the three main reasons against FCEVs are:
- the inferior efficiency of hydrogen as an energy storage solution (see graphic below)
- the current superior total cost of fueling a vehicle with hydrogen
- the higher impact on the environment because hydrogen is currently produced mainly from natural gas, until alternate renewable energy sources can be widely used.
Well, in the U.S., reason #3 is also valid for the electricity required to recharge battery packs at the stations, according to the U.S. Department of Energy:"ACCORDING TO THE U.S. ENERGY INFORMATION ADMINISTRATION, MOST OF THE NATION'S ELECTRICITY WAS GENERATED BY NATURAL GAS, COAL, AND NUCLEAR ENERGY IN 2019. (...) RENEWABLE ENERGY SOURCES GENERATED ABOUT 17% OF THE COUNTRY'S ELECTRICITY IN 2019."
However, many experts advocate in favor of hydrogen for other applications, such as industrial processes, heavy-duty vehicles (trucks, trains, ships), and long-distance VTOL flights.
Last May, Tesla announced the imminent launch of its new low-cost and low-cobalt / cobalt-free battery technology for its Model 3 sedan. On December 8, 2020, Volkswagen-backed QuantumScape revealed an SSD Li-ion battery for electric vehicles able to recharge to about 80% of capacity in 15 minutes, with a 12 years life span and at least 300 miles range in normal driving conditions.
Asia may hold the key to the potential success of hydrogen as an environmentally friendly energy solution for cars. In the meantime, you can speculate on the future by reading this recent report on the global fuel cell vehicles market 2020-2030.