Here is a list showing the number of returns for Mineral Oil Tax, the number of litres declared and the tax paid. Everyone in Ireland who owns a diesel-powered boat, and fuels it with green diesel, should be making a return; clearly very few are, and I suspect most of the litres (and the money) come from the hire firms. If that is so, their business is improving again.
| Year | Payers | Litres | Amount |
| 2010 for 2009 | 38 | n/a | n/a |
| 2011 for 2010 | 41 | n/a | n/a |
| 2012 for 2011 | 22 | 141,503.29 | €53,398.58 |
| 2013 for 2012 | 23 | 301,674 | €113,841.45 |
| 2014 for 2013 | 20 | 279,842.4 | €105,561.74 |
| 2015 for 2014 | 26 | 289,151 | €108,934.80 |
| 2016 for 2015 | 18 | 371,666 | €140,021.51 |
| 2017 for 2016 | 21 | 384,150 | €144,724.65 |
As far as I can make out, in the nine months ending 30 September 2015 (the latest figures I can find here) the Irish Sailing Association [PDF] received €899,000 and individual sailing persons a further €114,000 from the taxpayer. Furthermore, pretty well the entire cost of the inland waterways is met by the taxpayer.
Irish waterways history 
If the EU force Ireland to introduce tax on fuel for boats it will make boating a very expensive hobby, especially for anyone with a large engine. I wonder how many boats currently registered in the South will cancel their registration and seek refuge under a NI registration. The UK have no intention of introducing the tax.
1. The requirement is already law. However, it’s a law made [I suspect deliberately] unenforceable so that the state, in the interests of wealthy folk, can pretend to be obeying the law while not actually discommoding the rich. This is not, of course, surprising in this state, which works on mutual accommodation between different gangs of rent-seekers. Concealing that reality from foreigners (eg the EU and US capitalists) is one of the greatest problems for Irish governments.
2. I see no reason why the state should subsidise boat-owners (or participants in any other recreational activity, especially well-to-do ones).
3. Anyone who has a large engine and can’t afford it can sell the boat. Many boats were sold from Ireland after the Celtic Tiger died.
4. There is no boat registration in Ireland (save for the system operated by Waterways Ireland, which has nothing to do with Mineral Oil Tax).
5. The UK will shortly be out of the EU anyway, so it will be entirely free to devote itself to the career of piracy which its leaders seem to yearn for. However, hard Brexit will probably mean a hard border. Perhaps the Shannon–Erne Waterway could be mined.
bjg