The DNO
The UK electricity supply is managed by the District Network Operators (DNOs), also known as Energy Network Operators (ENOs) or Electricity Network Operators. These are different to the companies that electricity is purchased from. You can find out who is your local DNO is using this search tool 
.
To help the DNOs plan and manage the electricity supply infrastructure, an installer of a heat pump or electric vehicle charging point is obliged to inform their DNO.
Current process
The Energy Networks Association website is moving from a manual to online process for notification. The latest details are on the website, including a process flowchart .
There are two mechanisms:
- ‘Connect & Notify’
This is available if certain conditions are met, including the heat pump being included in the online database or spreadsheet accesed via the Energy Networks Association web-page. This method allows notification of installation to be done retrospectively. - ‘Apply to Connect’
This is the standard method which involves completing a form and is done prior to connection.
There don’t appear to any mini-split air conditioners in the heat pump spreadsheet mentions above. Checkmark's experience is that emailing the DNO with the make, model and power consumption details from the specifications of the mini-split unit has resulted in a reply saying to go ahead and connect. Because mini-split systems are low power compared to electric vehicles and whole house heat pumps, it is likely the DNOs do not consider them significant. Nevertheless, Checkmark recommend you inform the DNO as obliged.
Note that the purpose of this process is not to seek permission. It is so the DNOs can plan, and if necessary upgrade your service.
It is hoped that as this process moves fully online, it will become quicker and simpler.