An electric water heater can cost $400-$3,000 or more for complete installation of a conventional storage-tank model and $1,800-$4,500 or more for a tankless model (including a 220V/240V outlet). Electric water heaters typically cost less than gas units but are more expensive to operate. Solar water heaters cost $1,000-$5,000 or more, with installation usually included in the purchase price. A central, whole-house, gas tankless water heater can cost $800-$3,000 or more, without installation. Because tankless systems typically require the addition of a 220V/240V outlet and/or larger-diameter gas pipes than found in an average home, installation can bring the total cost to $1,800-$5,000 or more.