Installation Summary

The Sierra Club’s geothermal system uses a distributed geothermal heat pump (GHP) design tied to a common geothermal exchanger source.  The entire building contains several GHPs of differing capacities all piped to a common liquid distribution line.

The geothermal exchanger design for this building is called a “Class V Thermal Exchange Well Doublet”. The well water is pumped through an exchanger and then injected back into the aquifer with no change in water quality, making this system environmentally friendly and sustainable.

 Project Overview

Developer “All Florida Management Group” wanted to provide a home for the Sierra Club’s Florida Headquarters. They knew that Net Zero energy consumption be achieved by reducing energy consumption to the greatest extent possible.  This first step was to build a tight well insulated building.  Second was to put in geothermal heating and cooling.  With energy consumption reduced to the greatest degree reasonable, they placed enough solar photo-voltaic collectors to handle the reduced energy consumption.

Project Goals

Net Zero on-site emissions

    • Net Zero energy consumption
    • Low equipment cost
    • Longevity of HVAC system
    • Energy savings and environmental comfort

    Elimination/reduction of combustion/electric resistance heating


(2) AP035 Geothermal Heat Pumps (GHPs)

(1) AP071 GHP

Project Benefits

St. Petersburg’s first net zero energy, fully self-sustaining commercial office building almost four years ago, in December 2012. Like so many other energy independent buildings, the path was fundamentally simple; reduce energy consumption as low as possible, make up the rest with solar PV power. The following detail some of the benefits of the building’s features:

  1. No outdoor equipment
  2. More hurricane and storm resilient (no HVAC equipment outside)
  3. HVAC system longevity (a benefit of having equipment inside)
  4. No combustion or electric strip heating
  5. Noticeably superior comfort and heating and cooling modes
  6. Remarkable system efficiency at standard equipment pricing

Project Team

                    Project Name:

  • Sierra Club’s Geothermal Net Zero Energy Building, St. Petersburg, FL
    • Equipment Installed:

    (2) AP035 Geothermal Heat Pumps (GHPs)

    (1) AP071 GHP

    • Geothermal HVAC consultant:

    EggGeothermal Consulting, Kissimmee, FL

    • Contractor/Developer

    All Florida management Group, St Petersburg, FL

    • Manufacturer’s Representative:
    1. L. Spies Company, Tampa FL
    • Completion date:

    December, 2012