Can highly recommend Fieldhead Campsite in Edale. Not so sure about electrical hook ups - but they have a fridge you can use, and a plug for a hairdryer! Showers were hot and clean. The campsite is also based in the information centre, so you can go in and chat about what kind of walk you want, and they'll be able to help.
Great friendly staff on the campsite - two great pubs within 0.2miles of the site, and a pop up pizza tent over by one of the pubs that does the best stone baked pizzas you've ever tasted made fresh to order. Also a good breakfast cafe within a 2 minute walk.
Excellent walking, whether that's KinderScout, or popping over to Castleton. And if the weather isn't great, go down into one of the many caves over by Castleton. We went over at Easter, and we'll be heading back later in the year!
Pretty basic website:
http://www.fieldhead-campsite.co.uk/index.html
x