Good news.  There will be provision for the energy price cap to be extended to park home residents. as indicated below.  The detail is taken from Uswitch.

Is the price guarantee a cap on bills?

No, it’s a limit on the amount you can be charged per unit of gas and electricity. For the average household, this equates to a £2,500 annual bill, based on typical energy usage. Bear in mind your bill could be more or less expensive depending on your energy usage.

Who qualifies for the price guarantee?

The new cap will apply to all energy customers, including customers on standard variable - or default - tariffs, as well as those on fixed tariffs. Customers on heating oil, living in park homes, or on heat networks will also benefit.

Will the original discount on energy bills still apply?

Yes. The £400 payment to all homes will continue. Additional support, including the £650 payment to those on benefits such as Universal Credit, the £300 payment to pensioners, and the £150 rebate for those with disabilities will also go ahead.