Four a year, no sequences
Field notes from Boulder County roofs and attics
Written by the crew, with the arithmetic left in. If an article does not contain a number you can check, we do not publish it.
Whittier, microinverters under the cottonwoodsMost recent
Start here
ShadingWhat one shaded panel actually costs youA module in partial shade can cost a string inverter more than a module in total darkness. Here is why, with the arithmetic.Read it 
Heat pumpsThe only heat pump number worth arguing aboutNameplate capacity is quoted at 47 degrees F. Boulder's design temperature is 2. Here is how to read the table that matters.
RatesFour things to do before you buy a battery for your rateMost of the money in a time-of-use rate is available for free. Take that first, then decide whether storage is worth it.
AuditsWhy we test the house before we quote the roofHalf the homes we survey in Boulder County are leaking a third of their heating energy. Solar cannot fix that, and it should not have to.
Questions the articles do not answer
The shop phone is answered by somebody who has been on a roof. Ask an awkward technical question and see what happens.