Contact
Corrections are the most useful thing you can send.
Email banerjeeashutosh01@gmail.com.
Reporting an error
Include the page, the figure you believe is wrong, and what you think it should be. If it is a fuel price, the utility and the billing period help. Confirmed errors are published in the corrections log with the old and new numbers and the date of the fix.
Questions about the model
The methodology page carries the equation, the constants, the sources, and the conditions under which the model would give a wrong answer. If your question is not answered there, that is a gap worth closing and worth writing about.
Sending your own figures
The most valuable thing anyone can send is a real winter bill. The household dataset is the only first-hand evidence on this site, and it grows one household at a time. A winter month's kWh, your floor area, the month it covers and your state is enough to add a row. If your heat pump is on its own circuit or its own meter, say so, because that is the difference between a figure that is diagnostic and one that is indicative.
Nothing is estimated on anyone's behalf. Missing values are left blank rather than filled in, and every row records whether the householder identified a fault themselves or whether this site inferred one from their numbers.
Using the data
Every computed figure is downloadable as CSV and JSON under CC BY 4.0. No permission is needed and no email is necessary, though it is always interesting to hear what it gets used for.