Affordable Space Conditioning and Domestic Hot Water Systems with Low Emissions and High Performance
Research Team:
Franklin Energy, Harvest Thermal, AEA
Affordable Space Conditioning and Domestic Hot Water Systems with Low Emissions and High Performance
Research Team:
Franklin Energy, Harvest Thermal, AEA
Challenge
Heating and hot water represent two of the top three energy uses for California households, just ahead of cooling. Most heating and hot water systems in California use natural gas, resulting in GHG emissions that are incompatible with California’s climate goals. California needs cleaner, more efficient electric alternatives, however, electric HVAC solutions currently available are expensive to purchase, install, and operate. They often require the use of separate heat pumps for heating and hot water, and typical operation patterns overlap with grid peak times, drive higher bills for ratepayers, electric grid system costs, GHG emissions, and air pollution. Conventional heat pumps also use refrigerants with high global warming potential. There is an urgent need for electric alternatives that pollute less, are affordable to install and operate, and are suitable for retrofits into existing and new homes, to allow large-scale adoption in California.
Project Objective
The Project goal is to demonstrate the technical and economic potential for cost-effective combination systems to deliver cost savings and GHG emission reductions for new and existing homes. The Project will also validate load shifting performance for combined water and space heating, encourage industry acceptance of cost-effective combination systems through demonstration projects in new and existing homes, and communicate lessons learned to broaden adoption of the technology. As well as provide the technology, the proposed project will support contractors to advance market capacity for design and installation. A central control unit, designed for easy, consistent installation, will manage and optimize the operation of three main components: a single high-efficiency, low global warming potential heat pump; a standard, affordable hot water tank operating as a thermal battery; and an efficient air handler. The system is affordable, incorporating standard off-the-shelf components and only one heat pump. Load shifting using the thermal battery allows system operation to be optimized for time-of-use rates and minimize GHG emissions, while ensuring smooth, quiet heat delivery. High efficiency and load shifting deliver bill reductions of 30–40 percent (versus natural gas solutions), while reducing GHG emissions by 70–90 percent.
Impact
The proposed system reduces energy costs and GHG emissions, compared with baseline HPWH and heat pump space conditioning solutions by reducing operational costs by 10–30% compared to heat pumps and of 35 to 55% compared to natural gas technology and GHG emissions by 70–90% compared to conventional heat pumps without load shifting, and 85–95 percent compared to natural gas.