News of record-breaking temperatures filled the headlines in 2022. But amid the dire warnings about the effects of climate change was a signal of hope about our ability to reduce carbon emissions. A report from the International Renewable Energy Authority showed that, between 2010 and 2021, the global average cost of new solar power had declined by a staggering 88% while onshore wind had gone down by 68%. Defying persistently pessimistic forecasts, this data was further evidence of a wider trend towards a precipitous drop in the cost of renewables.

Given the acute energy crisis we face today, it sounds counterintuitive to say that we could be standing on the cusp of a new era of energy abundance. But renewable energy is cheap to produce, especially compared to current gas prices and, crucially, there is almost no limit on how much wind or solar energy we can use; the only real constraint is how quickly we can build the infrastructure and integrate supply. There is now, if we want to pursue it, the prospect of abundant, clean, nearly inexhaustible energy. But there is a catch: this renewable energy will only be abundant some of the time.

Currently, energy demand has peaks and troughs. But while it's relatively easy to ramp up production in a gas power station in anticipation of the nation boiling the kettle at half time during a World Cup match, the sun and wind don’t come with an on-off switch.

One answer to this challenge is to build extra renewable capacity so that we have plenty of power, even during the periods when natural supplies dip. But when renewables are going at full tilt, what could we do with this large amount of excess energy? An instinctive response is to suggest that we should avoid over-producing energy only to waste some of it, focusing instead on storage and flexible energy use. While both of those will be a critical part of our net-zero energy system, they are easier to do with a larger electricity supply: demand for electricity will increase dramatically anyway as we move towards net zero. Having more electricity than we need opens up more options for storage, as storage methods could afford to be less efficient and there would be smaller troughs in supply.

But there is also a risk here of thinking in a limited way. If energy was clean, cheap and plentiful, what other useful things could we do with it?

Abundant energy can be transformative, often in ways we don’t expect. So what opportunities might there be for using excess energy from cheap and widespread renewables? Perhaps first we should look to nations that already have abundant energy. A number of Middle Eastern countries use their generous endowments of fossil fuels to desalinate water in areas where freshwater is scarce. In Saudi Arabia, desalination accounts for nearly 20% of energy consumption. If done in a more sustainable way, with abundant renewables, new opportunities for agriculture could open up in many places. This model is also a potentially valuable way of adapting to climate change: where water becomes scarce, green desalination could provide an answer.

We could also use excess energy to fight carbon emissions directly. In practice, the landmark international Paris Agreement on climate change will require us to remove greenhouse gases from the atmosphere, not just stop emitting. One way of doing this is direct air capture powered by clean electricity. Already, experimental plants are being developed in Iceland with access to large quantities of cheap geothermal power. A problem at the moment is how much energy is used per unit of carbon removed. One study found that while direct air capture might help us achieve our climate goals, it might need to use perhaps a quarter of global energy demand by 2100. But if green energy is abundant everywhere, it creates scope to use this technology at scale and worldwide.

Of course, tackling climate change and energy supply through renewables might create new kinds of environmental havoc. Endless energy might enable people to more easily encroach on previously untouched habitats such as the poles or the deep sea, as energy is one of the resources needed to keep people alive in these environments. Yet opening these new frontiers could harm native species. We could also simply become ever more wasteful and fail to use excess energy for anything socially useful at all.

A future with abundant renewable energy is also far from assured. In 1954 the then-chairman of the United States Atomic Energy Commission, Lewis Strauss, pointed to a nuclear-powered future with electricity "too cheap to meter". But the technology never replaced fossil fuels in the way some anticipated. Similar predictions have been made about nuclear fusion since the 1950s and although recent strides mean that it might be somewhat closer than previously anticipated, we're still some way from widespread deployment.

Yet there are grounds for cautious optimism. New, improved forecasting techniques, which are more closely aligned with recent data, are beginning to point to a rosier future where renewable energy might be much, much cheaper, even in the face of growing demand, which is estimated to increase by nearly 90% by 2050. This represents a huge potential step change in productivity as part of the reduction in cost is down to improvements in efficiency – we can generate more energy with less hardware. And renewable energy’s greatest weakness – intermittency – might turn out to be a strength as we create excess supply that presents opportunities that were previously practically impossible.