La Porte, TX: the heat pump payback math
In La Porte, a heat pump pays for itself within a reasonable window. Against a like-for-like gas furnace and AC swap, going electric costs $1,000 more up front here (already netting out a $2,000 tax credit). La Porte's residents would see roughly $300 a year back in running costs, putting the payback around 3.3 years. The window here is reasonable, and it's specific to what La Porte actually pays for power and gas.
How cold La Porte actually gets
853 heating degree days pile up here every year, so La Porte barely has a winter to speak of; the cooling side runs to 3321 cooling degree days, where summers are severe enough that cooling can dominate the annual bill. The 99% winter design temperature here — the cold snap equipment must be sized for, not the seasonal average — is 32°F, against a record low of 21.4°F. That puts the seasonal coefficient of performance at 3.15 for the recommended standard unit. La Porte's winters don't get cold enough to need the cold-climate premium — a standard unit holds up fine. Source: NOAA station MORGANS POINT, 4.2 miles from La Porte — the closest one on record.
La Porte's running-cost comparison, in dollars
Modelled on a typical 2000-square-foot house, the heat pump draws about 686 kWh a year to keep it warm, plus cooling, for a combined electric bill near $568 a year. The gas furnace it replaces burns roughly 9 Mcf a year at 19.42 per Mcf here, for a running cost near $868 a year (electricity here runs 16.15¢/kWh). Priced as a standalone purchase rather than against a like-for-like replacement, equipment payback runs about 36.7 years, for a 15-year net position $3,494 ahead.
If your home heats with electric baseboard instead of gas
Not every home in La Porte has gas service. Swap the comparison to resistance heat instead of gas, and La Porte's answer improves. About $476 a year comes back this way, enough that the 11.6-year payback clears the $5,500 premium comfortably within the equipment's life.
Where La Porte ranks in this dataset
La Porte lands at position 2948 out of 3206 cities on heating severity (coldest is 1), and 1092 out of 3206 by population size (biggest is 1). That's the mildest third of cities covered, where utility rates carry more of the answer than climate does.
Next step for 38,046 people in La Porte
La Porte, Texas is home to about 38,046 people, and the figures above are the same ones a local HVAC contractor uses to size and quote a system — this site doesn't guess where a real quote would land, it just tells you whether it's worth asking for one. Given the math above, La Porte is a place worth lining up quotes ahead of a breakdown, not waiting for one.
Ask a local HVAC contractor for a quote before committing either way.
Reading further on this page's numbers
The methodology guide walks through exactly how La Porte's 3.15 seasonal COP and the rest of this page's numbers get built. The $2,000 federal credit baked into La Porte's number is explained, with the before-and-after math, in the tax credit guide.