You own only 1 metre below any land or property you have.
Is that still Ireland you're talking about? I ask because I understood the situation in Ireland was you basically owned a column of Earth the same size/shape as your patch of land, all the way down to the middle...
Here in the UK, I believe we own the top 6ft of any land, everything below (and all mineral rights regardless of depth, or lack thereof) are owned by the Crown, unless specifically sold.
When it comes to extracting water, I don't believe we need licences or anything like that, but we do have to pay "abstraction charges" in order to extract water in the first place. It's not metered, that I am aware of. We also have to pay to have water removed from our land - any rain run-off is considered to be grey water, and is sent to the water treatment works for release back into the nearest river/sea. This is charged based on a % of your water consumption (if you're on a meter), or rateable value of the property (a formula based on the value of your house, if you're not on a meter), or the size of the property for commercial premises. It's all ridiculously complicated, and mostly exists to keep a government department employed, I suspect.
I don't believe there are any restrictions on generators (other than noise nuisance laws, which a badass gen set might fall foul of) in the UK, but if you want to hook up an automatic switchover from grid power, it would have to be installed by a qualified electrician, and must use a break-before-make switch, to prevent any chance of back-feeding the local grid from your genset.