The new large-consumer can pay for the electricity it uses all by itself. If new generating capacity is required to meet the new, higher, demand, that should be factored in to the supply contract with the new large-consumer.
What is the rationale for jacking up residential retail prices? And what is it supposed to achieve?
If the argument is the whole sale price increases because there’s more demand, none of that new demand is coming from the pre-existing residential users, what does it have to do with them?