Your DNO owns and operates the power lines and infrastructure that connects properties in your area to the electricity transmission network. They're who you'll contact if you want to move your meters more than 1 metre (3 feet) or through a wall.
If you've experienced a power cut contact your DNO directly. You can also call 105 who will connect you to them.
You can find your gas network operator by your address. You can also call the Meter Point Administration Service on 0870 608 1524.
If you smell gas and are concerned, call 0800 111 999.