Let's return to rooftop solar. What factors influence our decisions to install it?
We know it depends on whether you live in metro, regional or rural areas, and factors like home ownership, apartment living and household income.
Today, we’ll examine another factor: politics.
Let’s dive in.
Reading time: 3.5 minutes
Data Note
Data about rooftop solar installations is published by postcode.
To find the dominant politics of the postcode, we mapped each one to a federal electorate. Then we categorised it by the winner in the last election.
Where postcodes fell into more than one electorate, we defaulted to the electorate with the largest overlapping land area.
It’s not perfect, so don’t go printing any campaign materials or anything based on this briefing, but it is illuminating.
Simple View
The chart below shows a simple view of the results.
Each dot represents a postcode. They’re grouped by politics. The vertical y-axis shows rooftop solar uptake (installed units per 10,000 people).
See how the average rate of solar installations is highest among Centre Alliance postcodes (light pink) and lowest among Greens postcodes?
Abbreviations key: LIB: Liberal; ALP: Labor; NAT: Nationals; XEN: Centre Alliance (formerly Nick Xenophon Party; in South Australia); LNP: Liberal National Party (in Queensland); IND: Independents; KAP: Katter’s Australian Party (one seat in House of Representatives); GRN: Greens.
It might sound weird to say postcodes in Greens electorates have the lowest rates of solar uptake.
But that's why we shouldn't look at politics alone.
In a previous briefing, we found rooftop solar correlates with owning your own home and having your own roof.
Households in postcodes among Greens electorates have low rates of both these.
- They’re 17 percentage points less likely to own their home (41% compared with 58% nationally)
- They’re 48 percentage points less likely to live in a freestanding house (32% compared with 80% nationally)
Let’s add politics to home ownership and standalone houses, and see what happens.
How To Read The Charts Below
You’re about to see a few scatter charts. Here’s what you should keep in mind.
Scatter charts compare two factors (or variables). One is measured on the horizontal x-axis and the other is measured on the vertical y-axis.
This gives us an instant view of how a thing (represented by a dot) performs against both variables.
We’re looking for patterns in the dots. Patterns mean the two variables are probably linked.
If the dots tend to move up and right, the two variables likely have a positive correlation (as one increases, so does the other).
If the dots move down and to the right, the two variables likely have a negative correlation (as one increases, the other decreases).
The closer the dots are to forming a straight line, the stronger the correlation.
Greens
Let’s put the postcodes in Green-held electorates on a scatter chart.
There is a remarkably clear pattern. The dots form one neat line that moves up and to the right.
This indicates a positive correlation. When these communities own their own home and roof, they install solar panels.
Nationals
Compare that with postcodes in National Party seats.
National postcodes have a higher rate of rooftop solar than Greens postcodes.
Yet, there is no clear correlation between solar uptake and home ownership or dwelling structure.
See how the dots are scattered and form no pattern.
Independents
Among electorates that voted Independent in the last election, a similar pattern emerges.
Ten independent candidates won their seats. Below are all the postcodes in those areas.
Seven of them were ‘Teals’, meaning they received funding from Climate 200 based on shared values of climate action, political integrity and gender equality and were not already in parliament.
If we separate Teal from non-Teal independents, we see the Teal postcodes are similar to the Greens. There’s a strong positive correlation between rooftop solar installations and owning your own home and roof.
If we separate the other three independent electorates, we see:
- Indi, a large rural seat in Victoria, has a similar pattern to the Nationals charts above.
- Clark (which covers the main metropolitan area of Tasmania, including Hobart), follows a similar trend to the teals.
Upshot
When it comes to the decision to install rooftop solar, different communities are motivated by different factors.
In urban communities agitated by environmental concerns, such as Greens and Teals electorates, solar uptake is clearly linked to practical matters such as home ownership and dwelling structure.
In rural communities, such as those in National Party electorates, the rate of solar uptake is higher but driven more strongly by other factors.
The question of what these factors are is a topic for another time. Do you have a hypothesis? Let us know!
Data Updates
Rooftop Solar Scoreboards
We’ve updated the monthly data about rooftop solar installations and there are movements in the national rankings.
Here are the top 3 postcodes for new installations in August 2024.
2765 (NSW)
Suburbs: Angus, Berkshire Park, Box Hill, Gables, Grantham Farm, Maraylya, Marsden Park, Melonba, Nelson, Oakville, Richards, Riverstone, Vineyard
- New solar units in August: 122
- Total units national ranking: 440 / 2117 (rose 50 places in August)
- Total units NSW ranking: 76 / 556
4655 (QLD)
Suburbs: Booral, Bunya Creek, Craignish, Dundowran, Dundowran Beach, Eli Waters, Ghost Hill, Great Sandy Strait, Happy Valley, Hervey Bay, Hervey Bay Dc, Kawungan, Kingfisher Bay, Kingfisher Bay Resort, Nikenbah, Pialba, Point Vernon, River Heads, Scarness, Sunshine Acres, Susan River, Takura, Toogoom, Torquay, Urangan, Urraween, Walliebum, Walligan, Wondunna
- New solar units in August: 105
- Total units national ranking: 160 / 2117 (rose 4 places in August)
- Total units QLD ranking: 41 / 363
4740 (QLD)
Suburbs: Alexandra, Alligator Creek, Andergrove, Bakers Creek, Bakers Creek, Balberra, Balnagowan, Beaconsfield, Belmunda, Blacks Beach, Caneland, Cape Hillsborough, Chelona, Coningsby, Coral Sea, Cremorne, Dolphin Heads, Dumbleton, Dundula, Dunnrock, East Mackay, Eimeo, Erakala, Foulden, Glenella, Grasstree Beach, Habana, Half Tide Beach, Haliday Bay, Hay Point, Homebush, Louisa Creek, Mackay, Mackay Bc, Mackay Caneland, Mackay Dc, Mackay East, Mackay Harbour, Mackay North, Mackay South, Mackay West, Mcewens Beach, Mount Jukes, Mount Pleasant, Munbura, Nindaroo, Noorlah, North Mackay, Ooralea, Paget, Planella, Planland, Racecourse, Richanna Heights, Richmond, Rosella, Rural View, Salonika Beach, Sandiford, Slade Point, South Mackay, Te Kowai, Telina Heights, The Leap, Timberlands, West Mackay, Wundaru, Yakapari
- New solar units in August: 101
- Total units national ranking: 1029 / 2117 (rose 17 places in August)
- Total units QLD ranking: 251 / 363