Resource

Auckland Rooftop Solar Resources (New Zealand)

Solar potential map of Auckland NZ

1) An average Auckland household consumes about 7000 kWh of electricity a year - what's your consumption?

2) Find your roof and click on it for your solar assessment.

3) Compare your electricity demand with your chosen PV system generation.

4) How much of the PV system generation would you consume yourself? This is your self-consumption rate.

5) Use the 'Solar assessment tool' panel for generation and economic estimates.

The user can select a building by clicking on it and the annual solar radiation on the best spots on the roof will be given for 4 different areas. Note that for example the 28 square metres with highest solar radiation could be located on several different segments of the roof - something to take in to consideration if planning to install a PV system! The user can then select a PV system size, by area. For reference, the corresponding approximate kW-capacity of a standard silicon crystalline PV system is also given.

After selecting a system size, the user can select the panel efficiency, either from the given default values that correspond to common PV technologies, of by inserting an efficiency value of choice. The tool will then calculate an average annual solar power output of the assumed system, taking in to account system losses of approximately 12%.

Finally, the tool gives an estimate of annual cash flow and net present value of the investment assuming a 25 year economic lifetime - with parametres that the user can change to better fit their individual circumstances, or just to test the impact of each parametre on the economic evaluation of the system.

PROJECT

This project is the result of collaborative research involving the Energy Centre, Auckland Council and the Centre for eResearch. With the LiDAR data provided by Auckland Council, a digital 3D model of the city with its topography, trees and buildings could be developed. This model was used to calculate the slope and aspect of Auckland rooftops at a spatial resolution of one square metre. This information along with the digital 3D model were used to calculate annual solar radiation on all the roof areas. With the assistance of the Centre for eResearch, a web-tool was developed to make these results publically available, along with an educational tool to estimate annual solar power output and economic feasibility.