Solar Panels - Number of Roofs
For this request, we worked with a number of assumptions. First, we defined “roofs suitable for solar panel installation” as roofs that are large enough for solar panel systems that can power an Australian house for a 24-hour period to be installed on them and that do not already have solar panels installed. Next, we then researched on how large a solar panel system that can power an Australian home for a day should be. Then, we researched on how large the roofs of Australian residential buildings are to know if they have enough room to handle the size of solar panel systems. Please find below a deep dive into this request as well as figures we triangulated.
SIZE OF SOLAR PANEL SYSTEM
We found from this data that in 2017, Australian households consumed, on the average, between 11.9kWh and 23.9kWh per day. The consumption is largely dependent on what part of the country they live. This source shows that a typical Australian home consuming 12kWh of electricity per day would require 2kW- 3kW solar system to power the household. If each 1.6x1 panel used generates 250W, then we triangulate these households will need a 19.2 square meters of roof space. A household that consumes double the electricity will require double the space. Therefore, the space requirement to install solar panel systems in Australian households is between 19.2 and 38.4 square meters.
SIZE OF ROOFS ON AUSTRALIAN RESIDENTIAL BUILDINGS AND THEIR NUMBER
This source gives us the sizes of roofs for three types of Australian residences:
Small houses — 100-150 square meters.
Medium houses — 150-200 square meters.
Large houses — over 200 square meters.
This information is important to determine if the solar panel systems can fit on the roofs. But, we still needed information for a number of houses. This source provides that information, putting the total figure of occupied dwellings at 9,901,496.
ROOFS SUITABLE FOR SOLAR PANEL INSTALLATION
To find the roofs suitable for solar panel installation, we first found the roof space required for installation. Our research showed that depending on the average daily electricity consumption, a residential building will need between 19.2 and 38.4 square meters of space. We also found that even the smallest Australian roof has 100 square meters of space. This means that all Australian roofs have space to install a solar panel system. We also got the number of occupied buildings. We now go back to our definition of “roofs suitable for panel installation” and give attention to the second part: These roofs should not already have panels installed. Here we find number of dwellings that already have installations. As at 2018, 1,811,485 houses have solar panel installations. Giving that our data for occupied dwellings is for 2016 and the data for installed panels is for 2018 and the fact shown here that between 2011 and 2016 the number of occupied buildings only dropped by 0.5%, we can assume that the number of suitable roofs is about 8,090, 011. That is 9,901,496 minus 1,811,485.
Defining roofs suitable for Solar panel installation and using this as the basis for our research helped us find that there are over eight million roofs in Australia with have at least 100 square meters of space. A solar panel system that will provide between 3kWh and 6kwH of electricity will require 20-40 square meters roof space.