footer-logo

This article is about a Dual-Source Heat Pump that also uses solar energy.  Al’s Plumbing, Heating & A/C in Plano, Texas provides maintenance & repairs for all brands of Central A/C, Gas & Electric Furnace, and Heat Pumps.  Additionally we sell and install new HVAC Systems from American Standard (same company as Trane), Ameristar (same company as American Standard) and Coleman HVAC (same company as York HVAC).

Al’s also provides full service plumbing maintenance, repairs and replacements for every plumbing component in your home.  Al’s sells and installs Rheem Professional Series gas & electric water heaters, and tankless water heaters.  Al’s is near your home in Plano, TX; Allen, TX; and Frisco, TX.  We service all homes in southern Collin and Denton Counties with no travel charges.

Call Al’s today to discuss any concerns or problems you have with your HVAC System or Plumbing.  We will arrange an appointment at your convenience and offer 24/7 Emergency Service.

A Dual-Source Heat Pump System

Uses Both Solar Panels + A Heat Pump

This System’s Solar Panels Create

Electricity  And / Or Heat 

PLUS

Extracts Heat From Outdoor Air (Air-Source Heat Pump)

OR

Extracts Heat From Underground Soil (using a Ground-Source Heat Pump)

home with solar collectors on the roof

Image Source: ShutterStock

Certain Models Of Air-Source or Ground-Source Heat Pumps

Can Be Connected To Thermal Or Hybrid Solar Panels

 

This Article Describes Residential Heating Using Renewable Energy From

The Sun + Outdoor Air

OR 

The Sun + Underground Soil

  • In milder climates an Air-Source Heat Pump can be combined with Solar Panels.
  • In colder climates, a Ground-Source Heat Pump can be combined with Solar Panels.
  • However, the heat-transfer pipes must be installed deeper and deeper depending on how cold the winters are at that location.  This installation is expensive.
  • In very cold climates, some home have both thermal Solar Panels + A Ground-Source Heat Pump.
  • In very cold climates, some homes have only thermal Solar Panels.  This system is much less expensive than a Ground-Source Heat Pump + Solar Collectors.

 

Click Here To Learn More About The Changing Face Of Electricity Generation From Fossil Fuels To Renewable Energy: AlsPlumbing.com Changing Face Of U.S. Electricity Generation

 

There Are 3 Types Of Solar Panels:

  • Thermal:  These produce only heat.  These have historically been used to provide residential hot water or to heat swimming pools.
  • Solar Cell (or PhotoVoltaic cell – PV):  These produce only electricity.  This electricity can be used to power an Air-Source Heat Pump.
  • Hybrid:  These produce both heat and electricity.

 

With Hybrid Solar Panels In Southern U.S. States, A Dual-Source Heat Pump System Works Like This:

  • During colder temperatures (when more heat is required than Thermal Solar Panels can produce) — the Hybrid Solar Panels generated electricity is used to power the Air-Source Heat Pump.
  • In this case, both the solar heat (from the thermal part of the Solar Panels) and electricity (from the PV part of the Solar Panels) are used to produce enough heat.
  • During milder outdoor temps, the Solar Collectors provide enough heat.
  • In this case, the Heat Pump outdoor unit does not run.  This dramatically reduces electricity consumption.
  • During times when the Heat Pump does not run, the electricity (generated by the solar panels) is typically rerouted into the home’s Circuit Breaker Panel.  That electricity is used in the home.
  • During times when the home does not need the electricity, it is commonly rerouted into the Electrical Power Grid.
  • Most Electricity Companies issue credits (against future electricity use) for electricity delivered into the Power Grid.

There Are 2 Types Of Heat Pumps:

1. Air-Source

central air conditioner outside unit

Image Source: DreamsTime

Shown: Air-Source Heat Pump

 

Air-Source Heat Pump (when heating)

During winter, an Air Source Heat Pump extracts heat from outdoor air.  The heat is collected within refrigerant fluid.  The warmed refrigerant fluid is pumped into the house where the HVAC System extracts the heat and sends it into the house.

air source heat pump diagram

Diagram Shows Air (with heat inside it) Entering The Air-Source Heat Pump.  The Heat Is Extracted And The Cool Air Is Released Into The Surrounding Air. 

Image Source: ShutterStock

 

Air-Source Heat Pump (when cooling)

During summer an air-source Heat Pump works identically to a Central A/C. 

During summer, heat is extracted from indoor air.  The heat is collected within refrigerant fluid.  The warmed refrigerant fluid is pumped outside the house into the outdoor unit.  The outdoor unit releases the heat from the refrigerant into the surrounding air.

Click Below To See A Diagram Showing A Heat Pump In Summer Cooling Mode AND In Winter Heating Mode:

Diagram Shows Heat Pump During Summer & During Winter

 

 

2. Ground-Source Heat Pump (also called Geothermal)

Ground-source Heat Pumps extract heat from soil below the surface.  This makes them are ideal for the northern U.S.  They are effective in areas with cold climates like Minneapolis, MN.

Ground source heat pumps are expensive to install because they require heat-transfer piping to be installed deeply into the ground.  About 1/2 of the total cost for a geothermal (ground-source) Heat Pump System is the installation charges for the underground heat-transfer pipes.

 

diagram of ground source heat pump installation

Image Source: ShutterStock

Shown: Diagram Of Ground-Source Heat Pump Installation

 

Heat Pumps Don’t Create Heat — They Extract & Move Heat (using a refrigerant fluid)

Heat Pumps Don’t Make Heat.  When heating, they Extract Heat From Outdoors and pump the heat within refrigerant fluid into the home.  The indoor HVAC unit blows air over the refrigerant pipes to extract the heat (from the refrigerant) and blow the heat into the home.

  • Air-Source Heat Pumps extract heat from outdoor air.
  • Ground-Source Heat Pump extracts heat from the soil beneath the surface.
  • Existing Dual-Source:  This heat pump extracts heat from both air & the ground.
  • NEW Dual-Source Heat Pump:  This heat pump extracts heat from both the air & the sun.

 

A SIDE NOTE:  Dual-Source And Dual-Fuel Heat Pumps Are Not The Same Thing

It nearly all cases, a heat pump is equipped with an auxiliary heat source that is powered by electricity or gas.  Some heat pumps have both electric and gas auxiliary heat.  These are known as Dual-Fuel Heat Pumps.  The auxiliary heat heat kicks in when the heat pump cannot extract enough heat from outdoor air.  Auxiliary heat can also for emergency back-up heat in the event the heat pump breaks down.

  • Dual-Source Heat Pumps extract heat from 2 outdoor sources.  This historically has been both air and ground.  The article is about newer systems that use gather heat from both the air and the sun.
  • Dual-Fuel Heat Pumps have both electric & gas auxiliary heat.  They extract heat from only the outdoor air OR from the ground below the surface.

 

Ground-Source Heat Pumps

And The Temperature Of Shallow Ground (30 feet deep) In The U.S.

Click Here To See A U.S. Map Showing Where New Ground-Source Heat Pumps Are Shipped:  Where Ground Source Heat Pumps Are Shipped (scroll down).

  • The soil temperature is 44°F in northern states in the center of the U.S. 
  • This temperature makes a ground-source Heat Pump effective for both heating & cooling in the northern U.S.
  • This is why Ground-Source Heat Pumps are more common in the northern U.S.
  • The soil temperature is 80°F in southern Texas. 
  • This ground temperature in southern Texas makes a ground-source Heat Pump ineffective for cooling. 
  • When cooling, an Air-Source Heat Pump works identically to a central a/c.
  • During winter in southern states, more heat is available within the outdoor air.
  • This is why Air-Source Heat Pumps are more common in the southern U.S.

Source: https://wellowner.org/geothermal-heat-pumps/q-what-is-the-temperature-of-the-available-ground-water/

 

Solar Assisted Air-Source Heat Pump

Heat Pump Technology PLUS  Solar / Thermal OR Hybrid Solar Panels

When heating, this Dual-Source Heat Pump extracts heat from both the outdoor air AND from the sun.   These Systems are more efficient during colder weather because (as temps get lower) there is less heat for the Heat Pump to extract from outdoor air.

  • The less heat within the outdoor air, the longer an Air-Source Heat Pump must run.
  • At low outdoor temperatures, a Heat Pump cannot extract sufficient heat from outdoor air.    With traditional Air-Source Heat Pumps, the auxiliary heat turns and works together with the heat pump.
  • At very low outdoor temperatures, the Heat Pump turns off and auxiliary heat produces all heat.   Once outdoor temps rise enough, both the heat pump & auxiliary heat to work together once again.
  • Note:  Outdoor temperature has little effect on solar panels.

 

The Efficiency Rate of a Combined Solar / Thermal & Air-Source Heat Pump System

A Forbes article stated:

  • Variable-speed, air-source heat pumps can currently be competitive with geothermal heat pumps in less less extreme climates.
  • With super-insulated, smaller newly built homes, the makers of geothermal (ground-source) heat pumps soon not be able to compete with today’s very efficient Air-Source Heat Pumps,
  • This is due to the cost to install a Ground-Source Heat Pump.

Source: https://www.forbes.com/sites/tomkonrad/2014/01/15/are-air-source-heat-pumps-a-threat-to-geothermal-heat-pump-suppliers/#3e8efbf5320c

 

For an Air-Source Heat Pump:

  • Maximum heating efficiency is October-December.
  • Minimum heating efficiency is February-April.

For Thermal Solar Panels:

  • Maximum heating efficiency is February-March.
  • Minimum heating efficiency is November & December.

Combining these two heating systems allows them to complement each other because each heat source is more efficient at different times of the year.

https://www.greenmatch.co.uk/blog/2015/07/combining-heat-pumps-and-solar-panel-heating

 

 

There Are Two Configurations Of Air + Solar — Dual-Source Heat Pumps:

  • Some Dual-Source Heat Pump Systems use water as the heat-transfer fluidThis is called an Indirect-Expansion system.
  • Some Dual-Source Heat Pump Systems refrigerant as the heat-transfer fluid.  This is called an Direct-Expansion system.

 

Direct-Expansion (Refrigerant) Systems Have A Distinct Advantage

  • With Direct-Expansion Systems, the solar panels alone can provide the heat needed during mild outdoor temps,
  • The heated refrigerant (from the solar panels) is pumped directly to the Indoor HVAC System Unit.
  • The Indoor Unit’s blower extracts the heat from the refrigerant and sends it into the home.
  • During milder outdoor temps, the Heat Pump outdoor does not run.
  • This notably lowers Heat Pump heating costs.

 

Solar + Air Source Heat Pump Systems Are Not Widely Available In The U.S. Yet

  • At present only the company Think Mechanical sells systems that would work in the far northern U.S.  These incorporate only Thermal Solar Panels (no heat pump).
  • Only the company Lennox HVAC sells Ducal-Source systems that work in the southern U.S.  These incorporate only PV Solar Panels + Air-Source Heat Pump.

Think Mechanical Thermal Solar Panel Heating

www.ThinkMechanical.com in Edmonton, Alberta, Canada, sells equipment for Solar / Thermal Residential Heating (no Heat Pump).   Solar thermal collectors use a fluid that is circulated through the system to collect thermal energy from the sun.   The heated fluid is pumped inside the house where the heat is released.   These systems are sold in Canada and are know for their effectiveness and efficiency in solar / thermal heating.   These products would work well in the far northern areas of the United States.   Think Mechanical’s system does not use a Heat Pump.

Click Here To Learn More About Think Mechanical’s Solar / Thermal Heating:  Think Mechanical Solar / Thermal Residential Heating

 

Lennox ® HVAC Air-Source Heat Pump + PV (electricity only) Solar Panels

Lennox® SunSource® is an Air-Source Heat Pump or A/C that is is powered partially by Lennox’s electricity generating Solar Modules® Solar Panels.   Specific Lennox systems are designed and equipped to be used with Lennox’s solar panels.  The solar panels provide some of the electricity needed.   You can chose to add more panels to further increase the amount of renewable (solar generated) electricity.

  • These panels are designed and intended to provide some of the electricity needed by the the HVAC System’s outdoor unit.
  • During times when the Heat Pump is not running, the electricity is rerouted into the Circuit Breaker Panel where it is used inside the home.

 

  • Heating & Cooling costs represent more than half of U.S. home’s total energy bills. **   This Heat Pump System provides a way to reduce cooling and (electric) heating costs.
  • Lennox’s Solar Modules® are rooftop Solar Panels that create electricity using the sun.  The electricity is sent to a Lennox® Signature ® Collection Solar-Ready®  Air-Source Heat Pump..
  • Lennox states this system “will save up to one half of total cooling and (electric) heating costs”.   For more details contact an authorized Lennox HVAC Company.
  • The cost of this system’s solar panels should be less than when installing enough Solar Panels to power the entire house (including the cooling & heating system).
  • At present only Lennox® Signature ® Collection Solar-Ready Heat Pumps or A/C’s can connected to their Solar-Ready Solar Panels.
  • The Signature ® Collection High-Efficiency outdoor HVAC unit will be notably more expensive when compared to a typical, standard-efficiency Heat Pump or A/C alone (of any brand).
  • The Solar Panels are an option at an additional cost.

 

Click Here For A Lennox®  Calculator To Compute Your HVAC Savings Using Lennox’s Solar Modules® Lennox HVAC Savings Calculator

 

Click Here To Learn More About Lennox®  Sun Source ® Solar Powered Heat Pumps & A/C’s: Lennox Sun Source Heat Pump or A/C

** Source: https://www.bobvila.com/articles/solar-energy-systems/

 

footer-logo

This article is about Dual-Source Heat Pumps.  Al’s Plumbing, Heating & A/C in Plano, Texas provides maintenance & repairs for all brands of Central A/C, Gas & Electric Furnace, and Heat Pumps.  Additionally we sell and install new HVAC Systems from American Standard (same company as Trane), Ameristar (same company as American Standard) and Coleman HVAC (same company as York HVAC).

Al’s also provides full service plumbing maintenance, repairs and replacements for every plumbing component in your home.  Al’s sells and installs Rheem Professional Series gas & electric water heaters, and tankless water heaters.  Al’s is near your home in Wylie, TX; Rowlette, TX; and Murphy, TX.  We service all homes in southern Collin and Denton Counties with no travel charges.

Call Al’s today to discuss any concerns or problems you have with your HVAC System or Plumbing.  We will arrange an appointment at your convenience and offer 24/7 Emergency Service.