Groninger Stadjerspas, a blockchain-based service for low income citizens

Municipality of Groningen
Paul Spoelstra and Bram Scholtens, Gemeente Groningen
BLING Mid-term magazine article
Reading Level
Readiness criterium
Business Need, Legal Requirements, Mandate


The Stadjerspas is a blockchain based service for low income citizens from the city of Groningen, the Netherlands. BLING interviewed Paul Spoelstra and Bram Scholtens about their experiences working with this blockchain-based service.

The Stadjerspas is a blockchain based service for low income citizens from the city of Groningen, the Netherlands. BLING interviewed Paul Spoelstra and Bram Scholtens about their experiences working with this blockchain-based service. Paul is project manager for the Stadjerspas for the municipality of Groningen. Bram has also been involved on behalf of Virtueel Groningen (a strategic programme to drive innovation in public service delivery).

What is the Stadjerspas? What does it do, and how did it come about?

Paul: “The Stadjerspas is basically a combination discount card and voucher system for citizens and families with low incomes in the municipality of Groningen. It has been around in different forms since the 90s, and we have had the system in its current form since 2016. Stadjerspas gives card holders access to social and cultural activities for free, or at a discount. The system subsidizes private services that low-income citizens would otherwise not be able to access, thereby promoting inclusivity. For example, you can go to the swimming pool, or get a discounted cinema ticket. It has a physical pass with a QR code that can be scanned, and it also has an online component – a web shop that citizens can use to buy tickets. At the moment it is only for citizens with low incomes – we are exploring the options to make it available to all citizens. This is already technically possible.”

The Stadjerspas runs on a blockchain application. Why did you choose a blockchain solution?

Bram: “At the end of 2013, the Stadjerspas was supposed to be withdrawn because of budget cutbacks. After discussions in the Municipal Council, it was decided to continue the Stadjerspas – but only for people with low incomes. We needed to produce an updated application in a very, very short time.”

Paul was required to get a working solution up and running within a few weeks, and he successfully managed to get the online web shop up and running. However, in part because of the time constraints, it initially had a lot of errors. “We were mostly able to fix those, but after a while we decided to look for a new solution”, Paul tells. “So we wrote a tender for a new solution, after we agreed on a program of requirements that we designed together with Stadjerspas users.”

What was the programme looking for? (in terms of transactions, authentication etc.)

The Dutchchain company offered us a solution that used blockchain. At the time it was a very new technology, and it looked promising because we could do secure transactions. We started using this solution in 2016, and after it was implemented the blockchain hype really started building – so we were suddenly invited to be on national television and to go to lots of conferences to speak about it.” Bram adds: “That was a nice side effect – it helped put Groningen on the map as a digital and innovative city.”

Can you tell us a little bit about how blockchain is used in the Stadjerspas?

Paul explains: “every user gets a personal wallet which is updated with credit once a year, and when new or temporary offers are added. For example, a citizen gets three tickets to the swimming pool in his or her wallet. When you go to the swimming pool, the QR-code is scanned. This transaction is stored in the blockchain. At the same time, an amount of money is made ready by the municipality to transfer to the swimming pool. The payment to the service provider is done in the usual way – it’s only the overview of the transactions that is put into the blockchain. At the end of each month, we receive an overview with all the transactions, and with that the invoices for all the service providers.”

Paul: “the system is hosted externally. Externally, we only have an email address and the QR-code. Apart from that, there is no personal information. This was done for security and privacy reasons – so if the system gets hacked, you’ll only have a bunch of email addresses. That is bad enough, but it is ‘less bad’ than being able to take a lot of personal information. The personal information we have about users is stored and managed by the municipality’s systems. So there is a connection between the external system and our own system.”

Can you give us an idea of how many people have used this service since it was started?

Over 20,000 citizens and service providers are registered in the program – there are around 4,000 smart voucher transactions every month.

Are there any downsides of working with blockchain?

Bram and Paul agree that the current solution has a few problems. Paul: “currently, we cannot undo transactions or delete accounts. This does not align very well with the right to be forgotten. So that is a problem. On a practical level, it is difficult when an error has been made. For example, sometimes people accidentally enter a wrong number, so they might buy three tickets instead of one. So sometimes we get emails from users who complain that they only have used the swimming pool once, but they have lost all their credit for the rest of the year. Our system is built in such a way that you cannot restore this per individual. In theory, we could have built it so you could update the existing ledger with a new transaction, so that the total is correct again. However that would have been very costly, so for the moment we have decided to take a different approach to solving these kinds of issues.”

What opportunities do you see for blockchain in the municipality in the future?

Bram: “well, as it is now, it is a nice to have, and it’s good to learn from it. But in this case blockchain doesn’t add a lot of added value. On the other hand, it doesn’t hinder us either. We can deliver a version of the Stadjerspas without using blockchain: there are other technologies that achieve the same results that don’t use blockchain. Of course, the technology and the range of solutions on the market has improved a lot since we started using this system three and a half years ago. Even so, there still is the matter of principle – if you can and should be a partner in an equal playing field as a government. A decentralised network can be challenging to use in our case.

Personally I don’t think a public blockchain is very suitable for most use cases for government, you’ll probably use a permissioned blockchain in some form instead. As a government, you are often responsible for many processes. So if we want to use blockchain for public services, you should be able to fix mistakes, for example. If that is not possible, then it is very hard to use.”

What do you think are the main issues organisations should think about when they are considering whether or not to choose a blockchain solution?

Both: “The solution just needs to work, and it must be easy to use.

If the solution uses blockchain, that is fine, but if the solution can
be delivered with just a regular database, then that’s ok as well.
For us, blockchain is not an end in itself. If a solution uses blockchain we are open to that, but for us, the most important thing is that the solution has to work well.”