Car-sharing for public administrations, state bodies, municipalities, institutions and all publicly funded institutions.
 
A large fleet of vehicles is owned by institutions receiving public funding. Unfortunately, I could not find the exact number. The official car is used to transport staff members on official journeys.
Just as e.g. www.prevoz.org effectively complements public transport and reduces costs and greenhouse gas emissions as private cars are better occupied, a similar public internal car sharing system could be set up for all public institutions.
For example, why would someone go to a meeting in Ljubljana alone when colleagues from another city and other institutions also holding meetings in the capital could go with them. As the entire fleet of these institutions is huge, there would be enough supply both ways, especially for the busier routes (major cities). It would be sufficient to announce at least a few days in advance where, when and how many free places will be available for the planned route. Examples such as shuttle services, car sharing abroad, etc. show that this is probably technically an easier solution.
The financial savings for the State and the reduced carbon footprint and pollution are just some of the benefits for the taxpayer, public servants could meet in person and exchange information on the road, which would increase the flow of information between institutions, they would be less burdened and there could be opportunities for possible better cooperation between them.
The greatest impact would, of course, be if it were made a legal requirement for all institutions to communicate on the same internal portal where and when missions are planned and how many vacancies they have available. Similarly to what is done in e.g. public procurement, where there is an obligation to bid, there could be an obligation to publish and then use this service if it provides at least a comparable result (e.g. arriving in or leaving Ljubljana at a certain time, etc.).
In combination with public transport, such a solution could become an example of transparency and a more efficient use of taxpayers' money, with an environmental twist. Perhaps frequent users of these services, including institutions, could also be rewarded financially in some way, e.g. as in other countries where cycling to work is rewarded with a slightly higher salary. All institutions could certainly save money on travel costs.
Unfortunately, I do not expect that such a thing is already possible in Slovenia. But perhaps we will find out what the real and apparent obstacles are.