There was a similar question a while ago but I’m not sure if it got resolved. 
There would be a few hurdles to clear:

- A legal entity (person or organisation) would need to be responsible

- Depending on the location surrounds, a suitable secure ‘box’ would need to be arranged for the meter

- There would be the need to connect to the supply cable which would involve work by the local DNO

So it could work out to be an expensive project 

Here is that previous thread by the way 

Thank you, this is very useful.

Hi @Mieko,

I can see that one of our forum volunteers has already given some great advice here. Hope you’re able to get this sorted.

Please let us know how you get on. It might be useful for anyone else in the same position. 

Not a smart meter, or a seperate supply, but something to consider and much less expensive..

If the gates are on a seperate circuit then I'm wondering if a solution here would be to get a private sub-meter/check-meter fitted just for the gates?
ie. Your own meter just metering what is used by the gates circuit for you to see and record (photograph) so that you could show that usage to your neighbours.

Maybe something like these:
https://www.tester.co.uk/rdl-qc4-60a-single-phase-electro-mechanical-meter-w-digital-display-reconditioned
https://www.jwsmartmeters.co.uk/shop/din-rail-mounted-meters/single-phase-din/sdm230dr-mid-single-phase-digital-kwh-meter/?gclid=EAIaIQobChMIxID2q5LB8QIVku3tCh3LFQlDEAQYDyABEgIsL_D_BwE

Talk to a local electrician about getting one fitted.

You would still be charged by your electricity company for the electricity used, but your own private/check meter will then tell you just how much of it was used for the gates only.
You would then need to negotiate/agree with your neighbours on how to split the cost of that gate usage.

Edit- Just another possible option.
If the power needed for the gates is low enough that it could be fitted with a plug and plugged into a normal domestic socket then you could use a simple smart plug to monitor what it is usimg.