Drake Landing Solar Community

How it works

There are 52 homes in this subdivision that contain an array of 800 solar thermal collectors. These solar collectors are located on the roofs of garages located behind the homes. During a typical summer day these collectors can generate 1.5 mega- watts of thermal power . A glycol solution (an anti-freeze solution; a mixture of water and non-toxic glycol) is heated by the sun’s energy and travels through insulated piping underground through a trench system to the heat exchangerwithin the community’s Energy Center. This is known as Solar Collector Loop. The glycol solution then transfers its heat to water in the short-term storage tanks. The District Heating Loop begins with water being heated in the heat exchanger at a temperature of 40-50 ° C within the Energy Center. This lower temperature is more efficient energy, as solar collecting is more compatible with lower temperatures. This increases the total amount of heat available to each home.

Borehole Thermal Energy Storage (BTES). The Borehole Thermal Energy Storage unit is 144 holes located 37 m (121 ft) below the ground and stretches over an approximate area of ​​35 m (115 ft) in diameter. The water returns to the short-term storage tanks in the Energy Center to be heated again in complete circuit. During colder months the water from the BTES passes to the short-term storage tank and is then directed to each home. Similar to a hot water tank, the heated water goes through a heat exchanger that blows air across the warm fan coil. Heat travels from the water through ductwork. When the temperature is reached on the thermostat, an automatic valve shuts the heat transfer unit. ^[7]

Energy center

The Energy Center building is a 232 square meter (2.500 square feet) building which began operation in 2007. ^[8] It is home to the heat exchangers, and controls. The Solar Loop Collector, the District Heating Loop, and the Borehole Thermal Energy Storage Loop pass through the Energy Center. Two horizontal water tanks occupy the majority of the space within the Energy Center. These tanks are 12 ft (3.7 m) in diameter and 36 ft (11 m) in length. The remaining space within the Energy Center houses pumps, valves, heat exchangers and other necessary equipment to operate and control the energy system. These tanks are known as Short-Term Thermal Storage (STTS). ^[7]

Borehole thermal energy system

The Borehole Thermal Energy System is located in the winter. It consists of 144 boreholes, which stretch to a depth of 37 m (121 ft). At the surface are joined together in groups of six to connect to the Energy Center. The entire BTES is covered by a layer of insulation, on which a park is built. When the water is being stored, it is pumped through the pipe series. The heat is then transferred to the environment and to the Energy Center. When the homes need heat, water flows to the center of the BTES field and picks up the heat from the surrounding soil. The heating water then goes to the short-term energy tank in the Energy Center and is pumped through the District Loop Heating to the homes. ^[7]

Sponsors and partners

This project was conceived by Natural Resources Canada’s CanmetENERGY in partnership with governmental organizations and Canadian industries. Of the $ 7 million needed for this project

• $ 2 million from federal government agencies.
• $ 2.9 million from the Federation of Canadian Municipalities and the Green Municipal Investment Fund.
• $ 625,000 from the Alberta Government. ^[9]

Community members

Homeowners were willing to pay for these energy efficient homes because it ensured high quality construction. Until the solar heating system Began working, ATCO Gas (an Alberta-based natural gas distribution company) heating costs fixed at $ 60 per month for the homeowners at the Drake Landing Solar Community. With rising fuel costs, this was a powerful incentive for homeowners to support the DLSC project. Even if the project had failed, ATCO Gas would have replaced the special hot-water furnaces with traditional natural gas ones. There was limited risk to the homeowners and this one to support the project. ^[10]

Local sustainability

The 52 homes in Drake Landing Solar Community are certified to Natural Resources Canada’s R-2000 Standard and Built Green ™ Alberta Gold Standard.

Costs and financing

• Each house sold for an average of $ 380,000.
• Homeowners are receiving an average of $ 60 per month bill solar utility for heating.
• $ 7 million for the initial start up of the Drake Landing Solar Community project.
• If this project were repeated it would cost $ 4 million, as approximately $ 3 million was for one-time research and development.
• Optimal community size would be 200-300 homes to realize the economies of scale. The number of systems would remain the same; only the number of boreholes would need to increase. ^[11]

International effects

A group of researchers from South Korea visited Drake Landing Solar Community in April 2012 to study the geothermal heating technology and how it can be applied to communities in South Korea, particularly ahead of the 2018 Winter Olympics in Pyeongchang . The main focus of this research is on the economics and reliability of the technology. ^[12]

Performance

On October 5, 2012 the DLSC set a new world record by covering 97% of space heating with solar thermal energy. ^[13]

See also

• List of energy storage projects

References