Solar Is Winning. The Grid Is Not Ready.
In 2023, solar power accounted for three quarters of all new electricity generation capacity added globally. The cost of solar photovoltaic panels has fallen by more than 90 percent over the past decade, making solar the cheapest source of electricity ever recorded in most markets. Wind energy has followed a similar trajectory. By almost any measure, the generation side of the energy transition is succeeding beyond what most analysts predicted ten years ago.
The problem is not generation. It is everything else.
The Transmission Gap
Electricity grids were built for a world of large, centralised power stations that could be dispatched on demand. The renewable transition is producing a world of distributed, variable generation: solar panels that produce power at midday and nothing at midnight, wind turbines that generate when the wind blows and nothing when it does not. Moving from the first world to the second requires not just new power plants but new transmission lines, new substations, new grid management software, and new storage capacity.
In the United States, the queue of renewable energy projects waiting to connect to the grid stretches to over 2,000 gigawatts. The wait time for grid connection has grown from under three years to over five in the past decade. Projects are approved, financed, and ready to build, but they cannot connect because the grid capacity does not exist. The International Energy Agency estimates that the world needs to add or refurbish 80 million kilometres of electricity grids by 2040 to meet climate targets. Current investment rates are well below what is required.
The Storage Problem
Variable generation requires storage. Battery costs have fallen dramatically, following a similar trajectory to solar panels, and grid-scale battery installations are growing rapidly. But batteries are currently most effective for short-duration storage, balancing supply and demand over hours rather than days or seasons.
Seasonal storage, the ability to capture energy generated in summer and use it in winter, remains technically challenging and expensive. Long-duration storage technologies including pumped hydro, compressed air, and hydrogen are at various stages of development and deployment, but none has yet achieved the cost and reliability profile needed for widespread adoption.
What Needs to Happen
Transmission infrastructure investment needs to accelerate significantly, which means permitting processes need to be faster and financing structures need to improve. In many jurisdictions, a new transmission line takes longer to permit than the renewable projects it would connect. That is not a technical problem. It is a governance problem.
Demand flexibility also has a role. Buildings, vehicles, and industrial processes that can shift their electricity consumption to times of high renewable generation reduce the burden on storage and transmission. Smart charging for electric vehicles, heat pumps with thermal storage, and industrial processes that can tolerate flexible scheduling all contribute to grid stability without requiring new infrastructure.
The generation revolution is real and it deserves the attention it receives. But the harder, less glamorous work of grid modernisation is what will determine whether that generation actually displaces fossil fuels or simply supplements them. The energy transition needs both, and right now only one is getting the investment it requires.