What will our transition to renewable energy look like?

The adoption of renewable energy in Australia has switched into high gear. The country’s energy future is about to look very different to the present. Origin Energy announced recently it will close its Eraring coal-fired power station – seven years earlier than expected. The site currently supplies 20 per cent of energy in New South Wales and will be decommissioned by 2025.

So, what will take its place? Origin plans to construct a 700-megawatt battery. Notably energy storage will play a key role as our power system changes and adapts. Many renewable energy alternatives are being developed, including wind (offshore and on land), solar, pumped hydro and even the solar panels on our homes – all smarter, greener ways to harness energy.

On a national scale, the Australian Energy Market Operator (AEMO) is anticipating a nine-fold increase in large-scale renewable energies, solar panels on homes to increase five-fold, and approximately 10,000 km of new high-voltage transmission lines to ensure these new energy sources reach customers. The AEMO’s current plan is to double the total energy capacity it delivers, so the faster the industry transitions the faster coal-fired power will be displaced. This means solar and wind, as well as pumped hydro and battery power, are about to take centre stage all around the country.

Making this shift, engineers have a substantial role to play in providing technical leadership. The big challenge of ensuring a fair transition for all and helping the most vulnerable in our communities along this journey, is one that requires a multidisciplinary approach that consults with all stakeholders.

We asked our experts to break down some of the key issues and challenges facing this transitioning industry.

One of the first technical issues to address is how we ensure the power grid is reliable. To do this, the grid needs to maintain what is called firm capacity and it cannot go below a minimum level of capacity. If it dips below its minimum, the system can become unstable – risking potential power outages. This is one of the biggest issues with renewable energy sources like wind and solar: They are dependent on environmental factors and not always consistent, creating difficulties in maintaining a reliable power grid.

This is where pumped hydro and battery storage come into the energy equation. As part of an integrated renewable energy solution, they provide that level of certainty so the system can maintain a baseline – independent of weather conditions. 

Ben McQueen, WSP’s Director of Energy, Central Region, describes the situation, “The legacy generation fleet of coal and gas doesn’t have this capacity issue. They aren’t reliant on the wind blowing or the sun shining. Meaning, whenever you need them, you turn them on and they’re available. This provides the reliability and certainty needed to manage the power system.

“The main challenge in transitioning to renewable energy is around the power system’s dispatch and control and how it effectively stores the energy from wind and solar.

“To make sure there is an ability to generate energy when we need it, providers are now supplementing the system with batteries and hydro power, because they give you that certainty of capacity.

“However, a big challenge for the market, and engineers, is the fairly aggressive timeframe needed to make all this happen. And on a social level, is there going to be equal access to renewables like expensive residential solar panels?”

Origin’s current plan for the Eraring Power Station site is to build the biggest battery storage in the Southern Hemisphere, which will ultimately support populations mostly in Sydney, Newcastle and Wollongong.

Alex McDonald, WSP’s National Technical Director of Approvals says, “There’s an important point around how much time we have from the decision point to actually flicking the switch on. It’s around a two-year process for planning approval of a high-voltage transmission line, taking into account the Environmental Impact Statement (EIS), seasonal ecological surveys, landowner negotiations, community consultation and easement acquisitions. Then once approved, you still have to actually go and build it. Overall, you are looking at a three- to four-year process, from the point of an approved financial decision to when you have something up and running.”

Ben adds, “At this point, there is the need for a strong approach to governance. We need to make sure the network or the distribution utilities are planned right down to that final connection level. There’s almost a dichotomy as you need the coal generators for a while yet. They're the ones keeping the system together, but at the same time with the penetration of renewables, it's both economically and technically impossible for them to continue providing that role.

“We’re in a situation where the biggest challenge for the industry is to figure out: How do we make that final switch? Even though we would like to run coal-powered stations less than we do, we can't because of the way our power system is currently managed.”

As the power system in Australia changes, the way it works must also adapt – and it needs to be equitable for all the communities it serves. The technology itself is developing so rapidly that a plan put in place today inherently needs to evolve to incorporate new innovations. Quite simply, we need to be Future Ready^TM.

Currently, Australia’s power system was designed around coal plants distributing power out from their individual locations. As we move forward, the system will have to adjust to varied and disparate power sources, including residential rooftop solar – which can have excess energy that needs to go back into the grid. This raises the question of battery storage, how does it best fit into the power system? As part of the responsibility of the electricity distributor (‘in front of the meter’) or does it sit with individual generators and perhaps even home owners (‘behind the meter’)? Should we be planning for large batteries in residential areas.

This future planning must look at how large batteries will be part of the solution and where they can be best located. Alex says, “Large batteries in residential areas come with their fair share of challenges – not only actual impacts on surrounding infrastructure and people, but the perception of those issues as well. Noise and electro-magnetic interference are two key issues that need to be carefully managed.”

While the goal of all these technologies is to reduce emissions, the question of how we get there is still a concern for many. The Australian Government just delivered its first budget since committing to net zero by 2050, and there is no new direct funding for renewable generation projects. It will however continue existing programs, particularly supporting industry investment into low emission technologies like hydrogen. Notably, the government is also giving $84 million to community microgrid projects, which can provide an affordable and reliable source of power in regional areas, meaning they will have greater agency over managing their systems. However, given the timeline needed to switch to renewables, the question of how we get there is more pertinent than ever?

Although there are many aspects to this discussion, the experts recognise the need for both strong governance and technical leadership working hand in hand. The hope is that together they’ll create the backbone of this new and equitable renewable energy network.