In reply to RX-78:
Hi,
When in particular are you thinking? in the winter and early spring for ski touring most refuges have winter rooms and in terms of water it's a case of melting snow. In the autumn some may not have a tap but a few like the refuge des Bans have access to a stream or river.
none will have electricity but solar works well here.
This site also has some information about some of the huts and some of the smaller cabins, although its not always up to date its a good starting point.
https://www.refuges.info/nav/18/massif/Ecrins/
If you let me know which huts and when I maybe able to give you an idea.
Cheers