Integrated energy demonstration project at Aurora Research Institute
In an effort to showcase available technologies for the production of renewable energy in northern communities, a demonstration project has been installed at the Aurora Research Institute in Inuvik. This system is built entirely from components readily available on the market and shows how individuals or communities could set up renewable energy sources and save on their energy costs.
1. Supplementing utility power with renewable energy
In this scenario the amount of energy supplied from the renewable energy source does not always cover the whole demand (e.g. due to the lack of sunlight in the arctic night or due to a lack of wind on certain days). To guarantee stable power supply to the user while reducing the consumption of fossil fuel and reducing the cost of power to the user, all the power produced by the renewable source is used and the shortfall is satisfied from utility power.
In the Aurora Research Institute demonstration of this scenario, the power generated by a wind turbine is passed through a rectifier (turbine produces 24V AC) and an inverter to consumer devices in the home, such as computers. Excess energy produced by the wind turbine is stored in lead acid batteries. If the energy demand exceeds the supply from the wind turbine, energy is supplied from the batteries. If no energy is available from batteries or the wind turbine, the energy demand is supplied from the utility.
2. Using renewable energy and selling excess energy to the utility
In this scenario the amount of energy supplied from the renewable energy source generally exceeds demand. The additional energy produced can then be sold back to the utility.
In the Aurora Research Institute demonstration of this scenario, the power generated by a PV array is passed through an inverter directly to the utility grid. Thus, all energy produced by the PV arrays is used in house and only the excess flows back to the utility. The benefit of this arrangement is that, should the PV array ever fail or need to be disconnected for maintenance, the energy used in the house would continue to be supplied by the utility.
3. Off-grid power
This shows a typical power solution where utility power is not available. This scenario assumes that all power used will be supplied by a single power source, in this case a hydrogen fuel cell, and that the power supplied will vary with the power demanded.
In the Aurora Research Institute demonstration of this scenario, the power generated by a hydrogen fuel cell (Ballard NEXA) is passed through a DC-DC converter and an inverter to supply consumer use.
It should be noted that the DC-DC converter was used because more appropriate equipment was not available.
Eliminating the DC-DC converter and using an inverter that can use the DC generated by the fuel cell directly would increase the system's efficiency.
