Use of the term "juice" Npower vs Westminster council

According to http://news.bbc.co.uk/1/hi/england/london/7869829.stm Westminster council are being taken to task by NPower over calling their recharging points "juice" points

Npower had used juice as part of a tariff name a number of years back.

But isn't juice a well known term for "power" or energy? If so isn't Westminster Council's use fair? It's just a point where you get juice. Entirely descriptive. I can't see how Npower could have exclusive use of that term

But then I'm not a lawyer - so perhaps someone can explain..