Help Creating "Consumption Calculator"

I want to make an electric consumption calculator in Excel based on entering the total dollar amount. If a utility company charges based on 4 tiers and has certain baseline allowances in each tier. Certain territories have an allowed baseline.

An example would be: Territory X is allowed 9 kW X 30 day billing period = Tier 1 baseline is 270 kW charged at 13 cents for a total of 35.10.

Tier 1 = 0-100% of baseline
Tier 2 = 101-130% of baseline
Tier 3 = 131-200% of baseline
Tier 4 = >200% of baseline

Tier 1 - 13cents/kW. Tier 2 - 15 cents/kw. Tier 3 - 32 cents/kw. Tier 4 - 36 cents/kw.

I want there to be a way to punch in the total dollar amount of the bill and Excel can calculate how many kW were used in each Tier. Is there a way to do this?

Any help is much appreciated!