Air Conditioners vs. heat pumps
Heat pumps can be interesting alternatives to central air conditioners.
Like air conditioners, heat pumps are electric-powered, but they use much less electricty, specially the geothermal heat pumps. And they provide both heating and cooling.
See: Heat Pumps Basics.
Air Heat pumps and Geothermal Heat Pumps
According to EPA, geothermal heat pumps provide electricity savings up to 72% (when compared to air-conditioning), while air heat pumps provide savings about half that value...
If your duct system is sufficient to support a high-capacity geothermal heat pump, and if the ground around your home supports the pre-conditions demanded by geothermal (digging a hole and installing a pipe system), this type of heat pumps can be an excellent investment to reduce cooling bills.
See: Installing a Geothermal Heat Pump
Geothermal heat pumps versus air conditioners/Furnaces Systems
Geothermal heat pumps involve an higher investment than central air conditioners: while a standard central air conditioning system may cost you between $3,000 and $6,000 (for homes with ductwork), an equivalent geothermal heat pump (installation included) can easily cost you something around $7,000 to $12,000 (an air-source heat pump cost is closer to that of a central air conditioning).
On the other hand, according to the Energy Savings Trust, a geothermal heat pump may provide energy savings of $1,300-$1,500 per year relatively to air conditioners (and will also avoid the production of around 4-5 tonnes of CO2 per year, that is, around 100 tonnes of CO2 over its lifetime).
Bottom Line
If your cooling bills are sufficiently high, since the energy savings provided by a geothermal heat pump may easily attain $1,000 per year (relatively to a central air conditioner/furnace system), you may recover the initial extra investment demanded by the geothermal heat pump in 6 years or less.
But all depends on details concerning your home, the installation of the heat pump and on your cooling and heating consumption.
See also:
Basics on Air Conditioning
Alternatives to air conditioners
Types of air conditioning
High-rated Air Conditioners
Ductless air conditioners
Room air conditioners
Portable Air Conditioners
Lowering AC bills
AC failures and improper operation
Maintenance
Professional Technician Services
AC filters
Refrigerant charge
Outdoor Coils Cleaning
Indoor Coils Cleaning
Blower Cleaning
Room air conditioner maintenance
Sizing Air Conditioning
AC installation
AC Manufacturers
