New Zealand’s largest solar water heating systems.
The YMCA’s Camp Adair, an outdoor education camp in the Hunua ranges south of Auckland, lays claim to having New Zealand’s largest solar water heating systems. The camp provides an adventure experience for up to 400 young people at a time and with kayaking, bushwalks and abseiling among the activities available, hot showers are in great demand. Guests use showers two to three times a day to clean and warm up. Clients range from school children to corporate groups and birthday parties. Open 24 hours a day, 365 days a year, the camp services approximately 30,000 guests a year, has eight full time staff and an average of 15 instructors at a time.
Promoting solar energy
The main site of the solar water heating system is being used as a solar education centre for the camp.
Hot water needs
The energy content of the water heated in a year is in the order of 95,000 kWh.
Hot water is used for the showers, hand basins (estimated at approximately 3,700 litres of hot water a day) and laundry and kitchens areas including two commercial dishwashers. Most of the hot water is used between 5.30am and 11pm with showers used regularly throughout the day.
Prior to solar water heating, water was heated by a mix of electric hot water cylinders and diesel fired mini boilers which were undersized for the maximum hot water demand by the camp. A decision was made to include solar water heating in the camp’s mix of energy sources to increase the efficiency of the camp’s hot water needs, given its high usage.
There are two separate solar water heating systems. The camp’s main solar water heater has 50 Edwards Titan collectors and provides hot water for the guest bathroom blocks and one kitchen. The smaller solar water heater two Edwards LX440 tanks with six collectors and provide hot water for one kitchen and staff facilities.
The hot water storage room houses two cylinders – one is a 5,000 litre solar pre-heated cylinder and the other is a 1,500 litre gas boosted hot water cylinder.
A pump circulates an anti-freeze fluid whenever the temperature of the panels is higher than the temperature in the pre-heated cylinder. The hot fluid then heats water inside the pre-heated cylinder via a heat exchanger. When hot water is needed and its not hot enough the gas burner operates in the second cylinder to bring it up to temperature.
The smaller SWH system includes two sets collectors and has a total area of 12m2.
This system includes two Edwards stainless steel 440 litre hot water storage cylinders.
YMCA directors say:
“Solar water heating is definitely worth doing but it’s important to go through the planning process properly; get a design first and ensure it is going to do what you want it to, including after its been installed”.