Case Studies
Rheem Heat Pump Water Heating & Beacon Pathways – A Smart Home for Future Generations
Sustainable water heating and sustainable living go together hand in hand as is the case with the Rheem HDi-310 Heat Pump Water Heater and research consortium, Beacon Pathways. Beacon Pathways is working to find affordable, attractive ways to make New Zealand homes more sustainable by changing the design, construction and renovation of New Zealand’s homes and neighbourhoods.
New Zealand Housing Foundation’s West Coast Rd subdivision in Glen Eden
Beacon believes that New Zealand homes can and should perform better – for the sake of our health, our resources and our nation. They call this being HomeSmart. Being HomeSmart is not about doing without, it’s about being smarter and doing more with less.
A pertinent example is the Housing Foundation’s recent HomeSmart pilot project in Glen Eden which has been built to see how energy, water and waste efficiencies can be made, to create a comfortable and healthy home, and to test the use of such features in future Foundation housing projects. A significant step in achieving these objectives was the installation of a Rheem HDi-310 Heat Pump Water Heater with up to 300% efficiency over traditional electric water heating and the potential to reduce the homeowners’ carbon footprint by up to 3.6 tonnes of CO2 per year.
This home is situated in the New Zealand Housing Foundation’s West Coast Rd subdivision in Glen Eden. Planned using ‘zipper lot boundaries,‘ the subdivision optimises solar gain by placing houses on southern boundaries for maximum northern outdoor space. The site comprises 77 lots ranging in size from 280m2 to 1247m2 and will contain housing in eight different styles when fully complete. Key components of the planned development include stream restoration, an extensive linked open space network, storm water treatment and attenuation wetlands, and extensive use of sustainable design features at an individual site level.
HERS Rating
The house was assessed under EECA’s Home Energy Rating Scheme. With comparatively modest changes, the rating increased from 4.5 stars in a standard Foundation home to a very commendable 8.0 stars.
Why Rheem Heat Pump Water Heating?
Heat Pump Water heating as a technology is able to offer significant savings over standard types of water heating.
Installation is simple and for a family home is usually more cost effective than solar – In this case there was not an ideal location for solar panels and as space was at a premium given the PV panels, HPWH really was the best option.
The Rheem HDi – 310 Heat Pump was specified as the home was designed for family use 250 – 300litres per day. Given the HDi - 310’s 1200 watt compressor, top down heating and 310 litre capacity the hot water demands of this household will be easily met.
The HDi - 310 has recovery and delivery performance similar to and exceeding that of a standard* 300 litre external electric cylinder – even though the unit was greatly reducing monthly water heating costs the comfort levels of the family were not compromised by the threat of running out of hot water *in summer due to higher ambient temperature the HDi – 310 outperforms a standard electric storage cylinder.
The unit was able to be situated outside next to the rainwater and grey water storage tanks in a pre planned area where visual impact and noise would not ever be an issue to the occupants or to neighbouring properties – this freed up valuable space within the home. (most homes in this development are on small sites).
A prominent brand with strong service back up was another reason for going with Rheem so that those living in the home would have peace of mind should any issues arise over the life of the water heater and possible replacement after that with latest technology available at whatever time that may be. It was important that companies chosen for inclusion in the Smart Home had a robust history and was assumed, would still be around in years to come.
HomeSmart features for better performance include:
Energy generation
- Photovoltaic energy production system, linked to the grid and capable of producing 2100kW per annum
Energy efficiency
- Insulated concrete slab foundation for thermal mass
- R4.6 ceiling insulation
- R2.6 external wall insulation
- PVC-framed double glazing
- External heat pump for hot water heating
- 4 star energy efficient washing machine
- 3.5 star energy efficient dishwasher
- 4 star energy efficient fridge/freezer
- LED and compact fluorescent lighting
- Stand-by easy reach switches or wireless controlled switches for appliances
- Window coverings
Water efficiency
- Low flow shower heads and taps
- Dual flush toilets
- 4500 litre rainwater tank for external use
- Greywater recycling system for re-use of bathroom and laundry water in toilets
- 4 star water efficient washing machine
- 4 star water efficient dishwasher
- Rain garden to reduce stormwater run-off
Indoor environment quality
- Enviro-friendly paint
- Linoleum used in bathrooms rather than vinyl
- Extraction fans vented to outside in kitchen, bathroom and laundry
- Opening windows for good ventilation
- Low profile, roof-mounted, solar powered ventilation vent
Waste
- Good construction waste management practices
- Multiple waste bins in the kitchen
- Recycled plastic carpet
Rheem Heat Pump Model Specifications
A551310 – 310 litre high recovery, top down heating, 2 piece integrated design. External installation.
* For full specifications download the Rheem Heat Pump Water Heater Fact Sheet here