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SCIS Podcast Episode 1: Bidirectional Chargers

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Friday, May 18, 2018

Anthony: I’m Anthony Colclough, and this is Urban Reverb, brought to you by the SCIS, Smart Cities Information system, at I know how my parents would feel if they thought I was bidirectional, but what about a bidirectional car? Today we’re looking at bidirectional car charging, or ‘vehicle to grid’ and the first question that springs to mind is: ‘What is it?’

Menso: Chargers of cars which go two ways, so they load, they charge the cars, but they also can uncharge the cars and add it to the electricity network.

Anthony: That’s Menso de Maar from Amsterdam, as he’s one of the few people in Europe actually using a bidirectional charger, I called him up earlier to find out about it.

Menso: Hello Menso de Maar. Yes, I’m fine, how are you?

Anthony: Menso explained to me how he’d gotten involved in this project.

Menso: I’m the managing director of a sports park in Amsterdam. The sports park is called ‘De Eendracht’, ‘cooperation’ in English, and what we’re doing in the sports park is all kinds of things with sports to achieve social challenges. What we also like is to participate in innovative projects, so we got in touch with Amsterdam Smart City, and they told us about this project, where they were looking for some place to put these chargers for cars.

Anthony: Okay, so bidirectional charging lets the electricity companies suck energy back out of my car battery when I’m not using it. But what’s the point? Marisca, from the project City-zen, which installed Menso’s bidirectional charger, filled me in.

Marisca: My name’s Marisca Zweistra, and I work in one of the Amsterdam projects for City-zen, which is the Vehicle to Grid project. Usage and supply of energy is changing. We used to have a very predictable usage of electricity, and also the supply could be managed perfectly in accordance to the demand. But with the arrival of durable energy, with solar and wind, the production has become much more dynamic. It’s not as easy to make the correct predictions. Sometimes we get congestion on the grid. This over production, this overload of the grid, is damaging for us, for the grid company, because the cables will deteriorate quicker than expected.

Anthony: Amsterdam isn’t the only Dutch city experimenting with this technology. As part of the project IRIS, Utrecht is also trying to find a way to integrate renewable energy seamlessly into its network. I got in contact with Muriel Pels to learn more.

Muriel: Yes, my name is Muriel Pels, I’m from the municipality of Utrecht. I’ve been strongly involved in the making of the lighthouse project IRIS. With the increase of solar energy and the demand for solar panels, there was a problem with the grid, that the grid could not handle these peaks. And there were also, of course, the lows, the valleys, when there was no solar energy. So, how to find a system in which you can organise this on a district level? And then we combined the solar energy production with the storage possibility in electric vehicles, because with the storage, the batteries in the electric cars you can store the solar energy when there is a peak in the supply of energy, and you can retract it for use when there is no solar energy.

Anthony: And it’s not just the Netherlands that are innovating with this new solution. Juha Karppinen from Helsinki, part of the mySMARTLife project, explained to me why bidirectional charging makes so much sense.

Juha: My name is Juha Karppinen. I am the innovation and business development team lead here at Helen. This is the natural kind of symbiosis of charging and batteries. Because each and every electric vehicle has a battery system built in, it just makes sense to use what we have. So if you already have batteries in EVs, then we should also utilise these to the maximum potential. Passenger Cars are mostly standing still, I mean the utilisation rate for a passenger car is less than 10%. 90% of the time it’s doing basically nothing, just sitting in a parking lot. So, with normal petrol cars, that’s just a waste of resources. With EVs, we can actually utilise this 90% of time to use this battery system. Your battery in your car by itself is always bidirectional, I mean you are regenerating energy as you are breaking, and you are using energy as you are accelerating. But the key is that when you park your car, if you have just a normal kind of charging device, you’re only receiving electricity. Basically filling up your gas tank if your talking about petrol cars. But if you have a bidirectional charger, you can also intermittently take energy back from your car. They have the vehicle manufacturers warranty that this bidirectional charging does not affect the warranty of the vehicle, or the lifespan of the battery. Nissan guarantees that it doesn’t affect it. And we will also make sure that you have enough battery charged always so that you can leave your office with confidence that you don’t run out of battery because of us. But what your car actually does: it helps our power system to cope with more renewable intermittent power generation. So basically, by allowing your car to participate in this small amount of adjustment, you are enabling us to bring in more renewable, more clean power generation to our power system.

Anthony: As with any new technology, no matter how good it looks on paper, there are still plenty of barriers that the cities trialling bidirectional chargers have had to face.

Muriel: Sounds relatively simple, but the problem is it’s so fine to match the supply and demand, both of the solar energy production, as well as in the reservation system of the electric vehicles, that you need a data platform to do this. You need to fine-tune when is the sun shining, when is the car reserved, how strong is the battery, how much use of energy do we expect at a certain time of the day… So you need to match all this information into an urban data platform. And that’s also what makes other applications possible in the future, that have not only to do with energy and mobility, but maybe also with waste collection or health issues, so that’s the basis for a lot more.

Anthony: But when it comes to barriers, that’s far from all. Back to Marisca.

Marisca: The amount of drivers that have suitable cars is a barrier; the technological status of the chargers, because we have not yet found a charger without issues. It’s really a work in progress, you ask for a charger and you get a charger and then you want to use it and then there’s something wrong that you need to fix.

Anthony: And she also pointed to a number of barriers presented by national and local legislation.

Marisca: Well, locally, we need to get a certain permit from the municipality to actually remove a parking space from the public domain, and every electric charging place is regarded as the removal of a public parking place, but ours is more so because we only allow certain contracted drivers to park there. So that’s a legislative hurdle.

Anthony: So barrier number one is taking over parking spaces.

Marisca: Also we have a problem with taxes, which has to be solved if we want to make this a real product in the grid. Because now there’s a strange situation that if you take electricity for your car you pay taxes and if you feed the same electricity back to the grid you pay taxes again, for the same kilowatt hour. So you pay double taxes. And then, of course, because it’s a bidirectional charger you go in, out, in, out, in, out, in, out all the time. So it can add up quite dramatically if you happen to park in a congested period.

Anthony: So we’re also looking for smarter taxes. But at the same time, we don’t want to pay out too much to drivers.

Marisca: Actually, that is one of the risks we have identified: That if the incentive is too good, to park at the bidirectional charger, if it’s so profitable to feed back to the grid, then you might get a problem with people parking there for free for five days, and we don’t want that. So that’s something that has to be changed. And for the project we have privacy issues, because we have only a limited amount of drivers. And normally if you collect data from a car or a household with respect to their energy consumption, you would anonymise it. But in the first weeks that we are running our first four chargers, we only have one charger per charging point. One of them is an electric minivan at a sports park…

Anthony: That’s Menso, who we met earlier.

Marisca: …It’s the only user at that point. One of them is a corporate driver at Price Waterhouse Coopers, and then there’s two civilians in the street. So then also, with regards to privacy, it’s either him or him. So that’s a kind of strange situation, and we now can solve it by asking the specific permission from the drivers to collect their data, because if you have that, then more is allowed. But if you extend the project to, let’s say 100 drivers, then we have to make some sort of decision on how to anonymise the data without losing valuable information. Because for some situations, for some measurements, it might be interesting to know if it’s a Mitsubishi Outlander built in 2013 or a Mitsubishi Outlander built in 2016, but if you add that information you might be able to tell if its John or Jack.

Anthony: But there’s another issue arising out of the use of public space.

Marisca: The property of the chargers is an interesting question, especially for Amsterdam, because in Amsterdam it’s normal that everything that you place in the public domain is immediately the property of the city of Amsterdam. And because these chargers are so expensive, that’s a strange situation. For these chargers that we have now, the City-zen project is paying, so that’s no problem for the city of Amsterdam, but if we ask them to support the grid with 100 of these chargers and they’re five times more expensive than a normal charger, and they are the property of the city of Amsterdam because they’re in the public street – then you can imagine that the city of Amsterdam will say, ‘Ahem, I don’t like them, I want the normal charger’. The property of the chargers is an issue, and also the way to deal with the extra costs for this. Is it the charge point operator, is it the grid company, is it the city of Amsterdam? Who is paying for… Who is gaining the benefits, and who’s paying for the extra costs.

Anthony: The penultimate issue relates to the restricted role that grid companies are permitted to play in the market place.

Marisca: Even more difficult because the grid companies are allowed only very limited activities, and one thing that we are not allowed to do is to pay customers for specific services. We can only get money from the customers, we cannot pay them. So, there’s always an extra party, but we are the ones who benefit the most, probably. So, there will be some kind of exchange of money from the customer to a certain party, be it the city of Amsterdam or the charge point operator, and then we have to get something as well, and I don’t know how that will work.

Anthony: Well, and there was one more barrier that was on everybody’s minds.

Marisca: If we want to make this a proper product to be placed in the grid, then the price of the charger needs to go down a lot.

Juha: Realistically, if we are looking at a roadmap for the future, I think the prices will have to come down to about one third of what this particular unit cost us. And, myself, I believe that bidirectionality is the future of the chargers. I mean if the prices come down, eventually they will reach the typical one-sided-chargers of today, and then there will be no reason to choose anything else.

Anthony: Marisca’s team defrayed the costs a little with an interesting purchasing mechanism, ‘best value procurement’.

Marisca: You don’t go into the market with a request for five chargers that are capable of doing this, this, this and that; that should be this and this tall, all those specifications, you don’t say anything about those specifications, but you say: ‘We want to test the effects of bidirectional charging on the grid, we want to test the effects on power quality, we want to see how much durable energy we can keep within the cable unit that the connection is in, we want to know the response time of the car to congestion signals, and all kinds of technical and economical specifications of what we wanted to know, that’s what we gave in the purchasing procedure. And we said we want four chargers minimum, and we have no more than €300,000. And that was a very interesting purchasing mechanism, because that made a sort of competition between the bidders. And I think that was a very good idea of us, because we would not have yielded the results we have now if we had just asked for all those specifications of the amount of kilowatts, and the amperage, now we could just say this is what we want in the end, and you have to help us to get there. We know what the goal is and you’re the experts and you’re going to guide us to the goal.

Anthony: The winning company even threw in some extra chargers to sweeten the deal.

Marisca: We asked for four, we are getting nine. That’s also part of the best value procurement, get more than you asked for.

Anthony: Marisca told me that trying to do all this design work that they ended up leaving to the company had been a dead end that took up unnecessary time, and energy. I asked the Helsinki team if there was anything that they should have done differently.

Juha: I think the location of the charger could perhaps have been a bit better. It’s not really off the grid or anything that the people would not find it, but the setting where it’s located, it’s not really the kind of place where you have lots to do while your car is charging.

Anthony: So the Helsinki charger is open to everyone. How many people are actually using it?

Juha: Maybe a dozen, or a bit more. It’s mainly because it’s only the Nissan and Mitsubishi models which are able to utilise the bidirectionality of the charger, but even more so because of the location of the charger. As enthusiastic as I am, as we in Helen are about the charger, I don’t think people will come from very far to experience the bidirectional charging. There’s nothing, no fancy lights flashing, or, you don’t get any kind of different experience form normal charging when you’re using this one.

Anthony: For all the projects, getting residents and drivers on board is central to their thought. Experience has taught cities that the adage, ‘If you build it, they will come’ is demonstrably untrue. So, what do you do to get people engaged in this new technology? Juha claims that in this regard, Helsinki has a natural edge.

Juha: I think it’s kind of a mentality that in Finland we want to try these kind of new things, and be at the very front row with new technologies.

Anthony: Marisca shared with me a number of methods used to get residents of Amsterdam on board with bidirectional charging.

Marisca: We knew that we had to be in a certain area of Amsterdam, and then we just decided to check out if there’s any community building where people gather for, I don’t know, the children’s doctor and the yoga class and stuff like that. And we found one that was actually hosting an evening on durability, and it was actually focussed on recycling, but we got ourselves into that meeting and we had a presentation about my project. And that was one of the best things we did. Because the people who were there were already interested in durability. They came there on their own initiative, actually, no one was forcing them, and I got my first drivers through that meeting. So that was a good advice that I would give to others, to not go around posting items in newspapers or on Facebook, or flyering in the whole neighbourhood, but just finding a place where the type of consumers that you need will gather automatically and get yourself known there. Very shortly after our installation we will have a meeting in the same community building. A nice evening with some drinks and some information that we will explain to the community what we did and why. And the good thing is that it’s not us that’s explaining it, but the municipality. We’ll have one of the deputies, who will be telling why Amsterdam has done this. To get the citizens really engaged in this, we decided it was better to have Amsterdam, who was already a very cooperative partner for us, to have them do the talking, because then also we can send out letters on Amsterdam paper, and that’s much more effective than if we print out our own letters, and everyone ‘What’s this?’ But the municipality they know.

Anthony: In terms of citizen engagement, the experience of Muriel Bells from the IRIS project was particularly interesting – how do you get bidirectional charging going in an area where nobody owns an electric car?

Muriel: Well, that’s something I can say something about definitely, because in Lombok, which is the district where the pre-pilot was taking place when we started working on the lighthouse project, there was 12 different points with smart solar charging points when we started the project. But that was a different district which was quite socioeconomically advanced. There were richer people who were quite innovation savvy, and highly educated, had some money to buy maybe an electric car. So we used that as a pre-pilot and now we are upscaling and replicating this in Kanaleneiland, which is a totally, totally different district in Utrecht. It’s a district that had a reputation as being problematic for being socioeconomically disadvantaged. Unemployment is fairly high, a lot of people who are illiterate for example – 30% cannot read or write in their own language even (which is often Moroccan). So this is a real challenge to try to extrapolate, you could say, the concept of smart solar charging from this fairly rich, highly educated Lombok district to Kanaleneiland. And to make it not private cars but shared cars, that’s another change. So what we chose is to make the whole approach more holistic, to involve employment, to involve quality of living in the neighbourhood, to involve what’s in it for the people other than contributing to mitigation of climate change, no, those are concepts that will probably not land in Kanaleneiland. We had for example University of the Arts as partner in the project to help us think about different ways of communication, and I think what we need to do in the end of course is to create the most benefit for the people, by for example reducing the cost of transport, which can be done by electric shared cars, and in the energy bill of course that people will have, and we try to engage people in the effects of this project on their neighbourhood. For example, getting people from the local professional school involved in the implementation of IRIS so that it’s connected not just with climate change but also with employment opportunities, and with being in a state of the art job that has a future, that is not going to be replaced by robotics but will probably have more and more opportunities in the years to come. So that’s, I think, a good way to make it a holistic and positive story that connects with people’s individual, local lives, actually. We look at who are the people who are most likely to adopt, what kind of lifestyle do they have, where are they, how can we find them, and how can we create, sort of, oil spills that in the end sort of merge into more of a movement. And that’s lessons that we have learned from other European funded projects in the past.

Anthony: So there you have it. Your car can support the use of sustainable energy. And you might make a little profit, or at least defray your costs into the bargain. If you’re interested in more information about bidirectional charging, or if you have some personal experience with it that you want to share, or even if you just want to tell me what you thought of our first podcast, you can email me at, that’s . For links, transcripts, and other information, please visit the smart cities information system at Thanks for listening.

Copyright Picture @Pixabay