From the Frontier Centre for Public Policy

By Ian Madsen

To store twelve hours worth of the 1.6 TW total installed global solar power capacity would cost about 12.9 trillion Canadian dollars

Solar energy’s promise of a green, abundant future is captivating—but beneath the shiny panels lies a story of unreliability, hidden costs, and grid instability.

Green enthusiasts endorse solar energy to reduce carbon dioxide (CO2) emissions from traditional energy sources such as coal, oil, and natural gas. The source of solar power, the sun, is free, abundant, and always available somewhere. However, these claims are misleading. Solar energy is costly and unreliable in ways its proponents commonly disguise. If adopted extensively, solar energy will generally make energy and electric power grids more unreliable and expensive.

The solar industry has burgeoned remarkably, with an estimated average compound annual growth rate (CAGR) of about 39 percent from 2021 to 2024. Earlier this century, the growth rate was even faster. As a result, global installed solar capacity has reached 1.6 terawatts (TW), according to the U.S. Energy Department. This capacity is theoretically sufficient to power a billion homes at 1.5 kilowatts per home. However, the term “theoretically” poses a significant challenge. Solar power, without affordable energy storage solutions, is only available during daylight hours.

The minimum amount of storage required to make global solar power truly “dispatchable”—i.e., independent of other backup energy sources—would be twelve hours of storage. Options include batteries, pumped hydro, compressed air, or other technologies. Since batteries are today’s standard method, the following calculation estimates the cost of the minimum amount of battery storage to ensure reliable solar power.

Twelve hours per day multiplied by 1.6 terawatts and dividing the result by one kilowatt-hour (kWh), we arrive at a final requirement of 19.2 billion kWh of storage. According to a meta-study by the National Renewable Energy Lab, the utility-grade cost of battery storage is C$670.99 per kWh.

To store twelve hours worth of the 1.6 TW total installed global solar power capacity would cost about 12.9 trillion Canadian dollars; a safer twenty-four hours’ storage would be double that. Total storage available in 2023 was, the International Energy Agency notes, approximately two hundred and sixty gigawatts (GW) of power – a tiny fraction of power production of 3.2 million GW in 2022, using figures from Statista.

No firms or governments can have the necessary storage to make solar viable even if the entire globe was involved, as the total global GDP was about C$148 trillion in 2023, according to World Bank figures. That is not solar’s only problem. The most harmful effect is how it undermines power grids. The misleading, ‘levelized’ near-zero cost undercuts traditional, reliable on-demand energy sources such as coal, natural gas and nuclear power.

Importantly, high solar and wind power output can make prices turn negative, as an Institute for Energy Research article noted, but can swiftly revert to high prices when winds calm or the sun sets, as the fixed costs of traditional power plants are spread over lower production.  Baseload traditional energy sources are essential because the frequent unavailability of renewables can be dangerous. Consequently, overall costs for customers are higher when renewables are included in the energy mix. Solar mandates in California made its power supply wildly erratic.

Without affordable energy storage, solar is a seductive illusion; its unchecked adoption risks turning power grids into unreliable, costly experiments at the expense of energy stability.

Ian Madsen is the Senior Policy Analyst at the Frontier Centre for Public Policy.