We interview Robert Griñó, professor at the UPC and member of the CARNET Academic Committee

September 2021

“Production costs prevent hydrogen from being a source of fuel for conventional vehicles at the moment”

“Public transport should be electric”

“The energy and environmental costs of moving someone around the city are less with an electric bus than with a gas one.”

Robert Griñó

Associate professor of the Department of Automatic Control (ESAII) of the UPC, and director of the Institute of Industrial and Control Engineering (IOC), Robert Griñó researches feedback control systems and is a member of the Academic Committee of CARNET, the mobility hub promoted by the UPC, SEAT and Volkswagen, and coordinated by CIT UPC.

You are an industrial engineer specialised in automation. How is your research connected with the automobile sector?

My connection with this area is associated with the electrification of vehicles. We focus on researching the processes of electrical energy conversion, and it is an area that is expanding.

You direct the Institute of Industrial and Control Engineering (IOC) of the UPC. What is the relation between the centre and research associated with mobility and the automobile industry?

At IOC we are focused on three areas: control, robotics and operations management, and the supply chain. In relation to mobility, we work on energy conversion in the electric vehicle and on electric chargers. We collaborate with companies in the power electronics and automobile sector. In addition, we research logistics topics, for example, in last mile distribution systems.

Autonomous vehicles are making way in the industrial and professional area but their introduction to the private vehicle market is lagging much further behind. Why?

In an industrial facility, the work environment is more or less known. Robotic vehicles move better in these spaces, but on streets and roads they encounter a myriad of situations, for example, of a climate nature. There are also legal aspects relating to the use of autonomous vehicles that have still not been resolved, such as cases of accidents.

You research the area of electric vehicles, which are still disadvantaged by autonomy, associated with batteries and their load. What does your work consist of?

We focus on the design of controllers for electronic power converters that vehicles are equipped with, particularly in the traction system. One of the latest projects on which we are working consists of generating one converter to manage energy exchanges between vehicles’ DC voltage buses. That is, between high voltage buses with batteries of between 300 and 400 volts, and low voltage buses of 48 and 12 volts, which feed auxiliary systems such as the lights and the air conditioning. We try to improve the efficiency of the system and maintain electrical quality.

Experimental prototype (right) of the converter (left, green box) of the Advanced control of on-board DC multibus systems in vehicles (coDCcar) project funded by the State Research Agency.

Are we about to see a real take off in electrical mobility?

In relation to the development of electrical mobility, there are problems that are being addressed. For example, charging is associated with the configuration of cities: most private cars do not have a garage in which to park, which makes the process of recharging batteries difficult. What’s more, the grid is dimensioned for current uses and consumption. If the demand for power increases, it will be necessary to change distribution elements, from transformers to cabling.

But there is a considerable advantage in terms of the reduction of emissions…

It depends on the pool of electricity generation in each country. For example, in Norway and in France, electrical energy is produced with very little CO2 generation. In the case of Norway this is because there is a high amount of hydroelectric generation, and in France it is because of nuclear generation. In other countries with systems that base their electricity generation on the use of coal and gas this is not the case.

Is the universalisation of 5G fundamental for the development of connected vehicles?

Connected vehicles need an efficient, fast, low latency channel of communication. And 5G enables a large volume of information to be handled that is sent and received in very short time intervals. This is critical in this type of vehicles, because a lot of decisions have to be taken very fast.

Part of your research is focused on the control of vehicles that travel in platooning mode. When will this technology complete the test phase and start to be implemented?

Inserting autonomous vehicles into the flow of traffic could benefit the entire system, and in our research group we are working on studying this kind of case from a theoretical perspective. For this technology to be a reality, we must be willing to introduce autonomous vehicles into the general mobility system. If we are talking about roads in good conditions, such as motorways, I cannot see any problem with lorries being able to move via platooning in the near future.

Robert Griñó

You have also researched fuel cells. Why hasn’t the use of hydrogen taken off in the automobile industry?

I have worked in the control of electronic converters to condition the electrical energy of fuel cells. Specifically, we focused on trying to ensure that the supply from the fuel cell is as constant as possible, regardless of whether the loads vary, to not damage it. Hydrogen has a recharging advantage compared to electric batteries, the system of refuelling is easier, but the problem of generation needs to be resolved because electrolysis has very low performance. Some buses use this technology, but I think that the production costs prevent hydrogen from being a source of fuel for conventional vehicles at the moment.

What will be the impact of introducing on a large scale electric and autonomous vehicles in cities?

Personal mobility vehicles, such as scooters and electric bikes, are a good solution for urban environments. In the case of scooters and bicycles, the efficiency of the system is very high: they move the user with small batteries that charge quickly, have reasonable autonomy and the energy cost of journeys is suitable for the desired purpose.

And in the case of public transport?

Public transport should be electric. The metro is and the tram. Buses that are moved by batteries are already a reality and in Barcelona there is at least one electrified bus line. Other countries have trolleybuses moved by electricity, but here we still see them as something old fashioned. We have to consider the efficacy of each one of the systems. I have the impression that the energy and environmental costs of moving someone around the city are less with an electric bus than with a gas one.