Electric car salary sacrifice: worth offering when most staff earn near the minimum wage?

UK care provider, around 4,600 employees, the large majority care workers paid within a pound an hour of the legal minimum. Head office is 280 people. A director has asked us to bring in an electric car salary sacrifice scheme, having had one at a previous employer.

My concern is that perhaps 300 people could ever use it, since sacrifice cannot take pay below the minimum wage, and that launching a benefit which 93% of the workforce is locked out of sends a poor message.

Has anyone in a low-pay sector launched one, and how did it land? Is there a way to do it without it looking like a head office perk?