Solar vs wind: the race to power up sustainable energy
Renewables are on the agenda for organisations, consumers and governments alike. A few years ago, convincing stakeholders of the virtues of renewables was an uphill battle, but now they’re seen as imperative.
And while the collective conscious has embraced the concept of renewables, questions remain. What’s the best source of renewable energy? Is it the low-cost-power-generating wind farm or the quick-build solar farm? What might a renewable future look like, and how will it happen?
Solar has emerged as a primary choice over the last few years. This comes down to the difference in gestation periods between solar and wind power farms. If you could get a wind farm up, from concept — to a development application (DA) — to construction, within seven years, you’d have done well. Generally speaking, wind farms require a solid decade, from concept to delivery. And we often find with wind power that a project may come to market two or three times over its life cycle. It can be shelved, and then it’ll come back. And then when it comes back, due to changes in technology and need, there may be a need to redesign and build larger turbines.
Harnessing the wind’s power is nothing new.
People used wind energy to propel boats along the Nile River as early as 5000 BC. By 200 BC, simple wind-powered water pumps were used in China, and windmills with woven-reed blades were grinding grain in Persia and the Middle East.
Of course, engineering and design have moved on somewhat since 200 BC, and another major contributor to the rapid increase in installed capacity comes down to the technological advances in our sector. These advancements have resulted in more extensive and more efficient wind turbines that can use intelligent technology.
So, is the answer still blowing in the wind?
Wind-generated energy is currently one of Australia’s primary sources of renewable energy, generating enough electricity to meet almost 8% of the nation’s total electricity demand.
The cumulative installed capacity of wind energy in Australia has been steadily growing and has more than tripled since 2010. This is partly due to it being one of the lowest-cost sources of new electricity supply in Australia. With the cost of utility-scale wind energy expected to continue to fall, new wind farms are anticipated to deliver electricity below $50/ MWh by 2030.
Or is it time to let the sun shine on solar?
Solar, on the other hand, is relatively quick to implement and reasonably low-impact. If done well, we can get from concept to start of construction in a little over a year.
The nature of the solar farm is fluid. The asset fulfils its purpose until it’s no longer required, meaning clients aren’t spending much capital on producing these types of investments. As engineers, it’s about designing solar farms that are fit for purpose but that are cost-effective.
Harnessing Australia’s solar potential is a no-brainer. Australians are leading the world when it comes to solar penetration through rooftop PV systems on homes. Reducing our electricity bills is the number one reason people are turning to this renewable energy.
Price certainty will always come up trumps.
So why have we seen such an influx in renewables over the past few years? The most straightforward and probably least popular answer from an industry perspective is around price certainty.
Of course, the corporate social responsibility element means all businesses want to be green, as well as the public’s perception and a shift in understanding.
But from my perspective and the renewable energy developer’s perspective, cost is king.
Until now, the challenge for energy, and carbon-intensive energy sources, has been price certainty. There’s variability in that. And that’s one thing the industry doesn’t like — cost variability.
Connectivity and transmission is the key to a renewable future.
One of the most significant challenges to face solar and wind generation is our ageing transmission network. It was created for coal-fired generators, emanating at the power station and transmitting to the high-demand areas.
Fast-forward to 2021, and we’ve got solar, and wind farms positioned in myriad locations across Australia — many not located near the coal-fired power stations and associated transmission lines. In many places the network, in essence, needs to be flipped, and together with battery storage, it’s our most significant challenge to overcome — how do we improve transmission networks across Australia?
This is where some issues around the stability of networks will arise. Put simply, we’re trying to feed too much power in at the wrong end.
And this takes us back to the all-important price point. For renewables to work effectively in the longer term, there needs to be a committed expenditure on transmission. And the critical issue Australia faces is quite simply this… who pays for it?
