Elderly people feared for their security after their electricity went off last night (Monday).
Tring councillor Nick Hollinghurst said occupants at the Dacorum Borough Council-owned residential home in Pond Close, Tring, realised the problem when heating failed and security doors stopped working.
UK Power Networks spokesman Jessica Gallagher said electricity supplies were interrupted at about 4.30pm, but all 19 customers affected had power restored by 11.15pm.
She said: “We would like to reassure customers that we worked to restore power supplies as quickly as was safely possible. We realise how frustrating it can be to be without power and apologise for any inconvenience.
“UK Power Networks operates a Priority Services Register for customers who are especially vulnerable in such circumstances, such as the elderly or those with medical equipment powered by electricity at home.”