Re-Visiting Carnot’s Theorem

The proof by contradiction used in physics textbooks is one of those arguments that appear surprising, then self-evident, then deceptive in its simplicity. You - or maybe only: I - cannot resist turning it over and over in your head again, viewing it from different angles. tl;dr: I just wanted to introduce the time-honored tradition … Continue reading Re-Visiting Carnot’s Theorem

How Does It Work? (The Heat Pump System, That Is)

Over the holidays I stayed away from social media, read quantum physics textbooks instead, and The Chief Engineer and I mulled over the fundamental questions of life, the universe and everything. Such as: How to explain our heat pump system? An astute reader suggested to create an 'animation' of the gradual evolution of the system's … Continue reading How Does It Work? (The Heat Pump System, That Is)

An Efficiency Greater Than 1?

No, my next project is not building a Perpetuum Mobile. Sometimes I mull upon definitions of performance indicators. It seems straight-forward that the efficiency of a wood log or oil burner is smaller than 1 - if combustion is not perfect you will never be able to turn the caloric value into heat, due to … Continue reading An Efficiency Greater Than 1?

How to Evaluate a Heat Pump’s Performance?

The straight-forward way is to read off two energy values at the end of a period - day, month, or season: The electrical energy used by the heat pump and the heating energy delivered. The Seasonal Performance Factor (SPF) is the ratio of these - the factor the input electrical energy is 'multiplied with' to … Continue reading How to Evaluate a Heat Pump’s Performance?