Rooftop solar can teach us three things about our electric car rollout

Bjorn Sturmberg, Kathryn Lucas-Healey, Laura Jones and Mejbaul Haque

Two rapidly growing technologies are roof- top solar energy and all-electric cars and other vehicles. Indeed we can contemplate using rooftop solar energy in excess of any domestic requirements for charging electric vehicles. This article discusses some issues relating to safety and quality, the dangers of shortcuts, timing, education, forward planning and coordination between the different technologies. [Ed]

Governments and car manufacturers are investing hundreds of billions of dollars on electric vehicles. But while the electric transport revolution is inevitable, the final destination remains unknown.

The electric vehicle transition is about more than just doing away with vehicles powered by fossil fuels. We must also ensure quality technology and infrastructure, anticipate the future and avoid unwanted outcomes, such as entrenching disadvantage.

In Australia, the electric vehicle rollout has been slow, and federal government action limited. But some state governments are working to electrify their bus fleets, roll out some public charging networks and trial smart vehicle charging in homes.

Australia’s world-leading rollout of roof- top solar power systems offers a guide to help navigate the transition. We’ve identified three key lessons on what’s gone well, and in hindsight, what could have been done better in a different manner.

Australia’s rooftop solar boom offers insights into the electric vehicle revolution.“Solar Bungalow” by Michael Coghlan is licenced by CC BY-SA 2.0

1. Price isn’t everything

Solar systems and electric vehicles are both substantial financial investments. But research into rooftop solar has shown that financial considerations are just one factor that guides purchasing decisions. Novelty, the concerns about climate change and a desire for self-sufficiency are also significant – and electric vehicle research is producing similar findings.

When considering the electric vehicle rollout, understanding these deeper motivators may help avoid a race to the bottom on price.

About one in four Australian homes has rooftop solar, with almost three million systems installed. The solar companies have often sought to highlight the low price of rooftop systems above other considerations. This bias has tended to create a consumer demand for lower- priced, lower-quality products – and has led to potentially hundreds of thousands of substandard Australian installations .

So what are the lessons for the electric vehicle rollout? Firstly, when planning public infrastructure where electric cars and other vehicles can be charged, the construction costs should not be the only consideration. Other factors such as night-time safety and access by disabled people should be prioritised. Shortcuts today will reinforce barriers for women and people with disabilities and create complex problems down the track.

Like rooftop solar, the point of sale of electric vehicles offers a unique opportunity to teach customers about the technology. Companies, however, can only afford to invest in customer education if they aren’t too stressed about margins.

“Smart” charging is one measure being explored to ensure that the electricity network can handle future growth in electric vehicle uptake. Smart chargers can be remotely monitored and control- ed to minimise their impact on the grid.

The point of sale is a pivotal moment to tell new owners of electric vehicles that their charging may at times be managed in this way.

Electric vehicle charging infrastructure should be safe and accessible. “Electric Cars Charging Station” by PapJeff is licenced by CC BY-NC 2.0

2. Plan ahead

The uptake of rooftop solar in Australia has been a raging success. In fact roof- top solar is now then largest generator in the national power system.

This raises issues, such as how rooftop solar systems will respond to a major disturbance, such as the failure of a transmission line. And a large amount of solar power feeding into the grid can also challenge electricity network infrastructure.

In response, electricity networks have implemented changes such as limiting solar exports and therefore, returns to solar system owners, and charging fees for exporting solar.

Such retrospective changes have been unpopular with solar owners. Therefore in order to maintain reliable electricity supplies, and avoid angering consumers, it’s vital to plan where and when electric vehicles will be charged.

If every motor vehicle in Australia was electric, this would add about a quarter to national power demand. The rise in demand would be greatest near the bus and logistics depots and ultra-fast high- way chargers.

Timing is key to maximising the use of a network connection without overloading it. For example, if everyone charged their vehicle in the evening after they get home from work, as this would create pressure at this peak time.

Governments and electricity providers should encourage electric vehicle charging during the day, when demand is lower. This might mean, for example, providing vehicle charging facilities at workplaces and in public areas.

Until Australia’s power grid transitions to 100% renewables, the use of solar energy should be strongly encouraged. This would ensure the vehicles were charged from a clean, cheap energy source and would help manage the challenges of abundant solar.

The question of road user charges for the drivers of electric vehicles is another example where it’s best to avoid retrospective changes. Such charges are necessary in the long run and best introduced from the outset.

Vehicle charging during the day, when power demand is lowest, should be encouraged. “Electric vehicle charging” by UBC Media Relations is licenced by CC BY-NC 2.0

3. Coordination is key

Electric vehicle policy spans several government portfolios: transport, infra- structure, energy, planning, environment and climate change. Nationally, and from state to state, different government ministers are in charge.

This makes coordination difficult, and creates the risk of policies undermining each other. For example, one policy might encourage the charging of electric vehicles from rooftop solar, in order to reduce carbon emissions. However because solar energy is so cheap, this might encourage more private vehicle use, which worsens road congestion.

So policies designed to encourage the uptake of electric vehicles should not come at the cost of creating more attractive and efficient public transport networks.

And new technologies can entrench societal disadvantage. For example, the rooftop solar rollout has often excluded people who could not afford to buy the systems. Without policies to address this, the electric vehicle transition could lead to similar outcomes.