Solar energy has an advantage that no human-built power plant can replicate on the same scale: an extraordinarily abundant natural resource. The solar radiation reaching our planet represents an energy potential far greater than humanity’s current needs.

Yet theoretical abundance does not mean that this energy is available in the right place at the right time. A photovoltaic panel generates electricity when the Sun is shining, while our homes, businesses, transportation systems, and infrastructure need electricity 24 hours a day.

This is where one of the major challenges of the energy transition lies. The question is no longer simply how many solar panels we can install. It is about determining how to transform intermittent generation into a reliable, accessible, and sufficiently flexible electricity system capable of meeting demand at all times.

This issue, closely related to the questions explored by Léwis Verdun in Will Solar Energy Be Enough to Power Everything?, encourages us to look beyond the photovoltaic panel itself. Energy storage, electricity grids, the complementarity of different energy sources, and changing patterns of consumption will largely determine the true role of solar power in our energy future.

The Real Challenge of Solar Energy: Producing Electricity at the Right Time

The growth of photovoltaics has been remarkable. According to the data presented in Léwis Verdun’s book, solar power now represents a major share of new electricity generation capacity installed worldwide. The considerable decline in production costs is naturally contributing to this acceleration.

But installed capacity and electricity available at all times are two different things.

The output of a photovoltaic installation varies throughout the day. It increases in the morning, generally reaches its maximum during the sunniest hours, and then gradually decreases until disappearing at night. In addition to this daily cycle, there are variations caused by weather conditions, seasons, and geographical differences.

Electricity consumption, however, follows a different pattern.

A city continues to function after sunset. Trains keep running, hospitals remain open, data centers continue processing information, and households keep consuming electricity. With the progressive electrification of transportation and heating, new electricity needs are also emerging.

A high penetration of renewable energy therefore requires us to bring together two curves that do not naturally coincide: the production curve and the consumption curve.

This is precisely why the future of photovoltaics depends just as much on the infrastructure surrounding solar panels as it does on the panels themselves.

Energy Storage Is Becoming Strategic Infrastructure

Energy storage is one of the most obvious responses to the mismatch between solar generation and electricity consumption.

The principle seems simple: store excess electricity produced during sunny periods so that it can be used when solar generation decreases. In practice, however, different needs require different technologies.

Lithium-ion batteries are particularly well suited to managing fluctuations over a period of several hours. They can, for example, store part of the photovoltaic electricity generated in the afternoon and release it during the evening peak in demand.

Other technologies aim to reduce costs or dependence on certain materials. Sodium-ion batteries, for example, are attracting growing interest for stationary energy storage.

For longer periods, other solutions can play a role, including pumped-storage hydropower, thermal energy storage, hydrogen produced through electrolysis, and emerging long-duration storage technologies.

The challenge, therefore, is not so much to find one universal battery as to develop a portfolio of complementary solutions.

A household solar installation does not face the same constraints as a major city or a national electricity grid. Similarly, shifting a few kilowatt-hours from midday to the evening is very different from storing enough electricity to compensate for several days of low renewable energy production.

The expansion of solar power is therefore driving a broader transformation: storage is gradually evolving from a complementary technology into a strategic component of the electricity system.

Why Smart Grids Will Be Just as Important as Solar Panels

Producing and storing more electricity is not enough. That electricity must also be transported efficiently.

Historically, electricity grids have generally been designed around large, centralized generation facilities. Electricity was produced by major power plants and delivered to consumers through transmission and distribution networks.

Photovoltaics are partly transforming this architecture.

A solar power plant generating several hundred megawatts can supply the grid, but a homeowner with solar panels on a rooftop can also become an electricity producer. Businesses, farms, and local authorities can do the same.

The grid must therefore manage a multitude of variable and sometimes bidirectional electricity flows.

This transformation highlights the importance of smart grids. Through data, automation, and more sophisticated management systems, they can better anticipate electricity production and adjust certain forms of consumption.

Consider a simple example. An electric vehicle may remain parked for several hours. Charging does not necessarily need to begin the moment the driver plugs it in. If the grid has abundant photovoltaic generation at midday, charging can be scheduled to take advantage of this period.

The same principle can apply to certain water heaters, industrial equipment, or air-conditioning systems.

Demand flexibility then becomes an energy resource in its own right.

Instead of constantly adjusting electricity generation to immediately follow demand, an intelligent system can shift some consumption toward periods when renewable electricity is abundant.

This development can help reduce storage requirements while making it easier to integrate greater quantities of solar energy.

An Energy Mix Rather Than a Single Energy Source

Imagining the future of electricity as a competition designed to identify one winning technology often leads to an overly simplistic view.

A resilient energy system relies more on complementarity.

Solar power generates large amounts of electricity during daylight hours. Wind power can continue producing electricity at night. In some regions, hydropower provides dispatchable generation as well as significant storage opportunities. Other low-carbon generation technologies can also help ensure continuity of supply depending on the characteristics and energy choices of each country.

The challenge is therefore to build an energy mix capable of combining several essential qualities: a low carbon footprint, reliability, controlled costs, resilience, and accessibility.

Diversification also offers a geographical advantage. Not every region has access to the same natural resources.

A very sunny area may rely heavily on photovoltaics. A mountainous region may benefit more from hydropower. Some coastal areas may have particularly favorable conditions for wind energy.

Electricity interconnections can then make it possible to share some of these resources between different regions.

The energy transition thus becomes a system-level challenge rather than simply a technological one.

The Key Levers for Making a Solar-Based System More Reliable

Integrating more photovoltaics while maintaining a reliable electricity supply requires several measures to be implemented simultaneously.

The first involves storage. Batteries, pumped-storage hydropower facilities, and thermal storage systems can preserve some of the available energy and release it when solar generation decreases.

The second relies on smart grids. These systems make it possible to better balance generation and consumption by adapting certain uses to periods when renewable electricity is abundant.

Interconnections between different regions are another important tool. When one area produces more electricity than it consumes, some of that surplus can be transported to another area where demand is higher.

Finally, diversifying the energy mix makes it possible to complement solar generation with other sources, including wind, hydropower, and other forms of low-carbon electricity generation.

These solutions must also be accompanied by greater attention to energy efficiency. The easiest electricity to produce, transport, and store is ultimately the electricity we can avoid wasting.

For individuals, businesses, and local authorities, several actions can support the development of solar power:

  • improve the energy efficiency of buildings and equipment;
  • schedule certain uses during periods of high renewable electricity generation;
  • develop energy storage where it is economically and technically appropriate;
  • strengthen and modernize electricity distribution networks;
  • encourage the recycling of solar panels and batteries;
  • design infrastructure while considering its entire life cycle;
  • diversify electricity sources to reduce dependence on any single technology.

This final consideration is essential. The energy transition cannot be assessed solely on the basis of the CO₂ emissions produced while a piece of equipment is being used. Raw material extraction, manufacturing, transportation, lifespan, recycling, and social conditions throughout supply chains must also be taken into account.

Solar Power Is Also Transforming the Way We Think About Electricity

For more than a century, most consumers have used electricity without needing to know exactly when it was generated. The large-scale arrival of variable renewable energy could gradually change this relationship.

In the future, electricity prices, electric vehicle charging, and the operation of certain appliances may become more closely linked to energy availability.

This does not mean that everyone will have to constantly check the weather before switching on an appliance. Automation can handle much of this decision-making.

A home equipped with photovoltaic panels, a battery, an electric vehicle, and an energy management system could, for example, automatically decide whether to consume, store, or feed electricity into the grid according to available generation, anticipated needs, and grid conditions.

At the scale of an entire city, the same principle becomes far more powerful.

Thousands of buildings, batteries, and vehicles can form a distributed system capable of absorbing electricity surpluses and reducing certain peaks in consumption.

The innovations discussed in Will Solar Energy Be Enough to Power Everything?, such as perovskite solar cells, agrivoltaics, and new energy storage solutions, take on their full significance from this perspective. They are not simply new products: they are contributing to the construction of a fundamentally different energy system.

The success of solar energy will therefore not depend solely on the number of panels installed. It will depend on our ability to build an infrastructure around them that can store electricity, transport it efficiently, and intelligently adapt part of our consumption.

Photovoltaics have considerable advantages: an abundant resource, increasingly competitive costs, and a wide variety of applications. At the same time, their expansion highlights the other essential challenges of the transition: energy storage, modernization of the electricity grid, recycling, infrastructure, technological complementarity, and social justice.

This system-wide perspective allows us to move beyond an overly binary question — “Can solar power provide all our energy?” — and ask a potentially more useful one: how can we make the most of its immense potential while building a reliable and sustainable energy system?

This is precisely the nuanced perspective developed by Léwis Verdun in Will Solar Energy Be Enough to Power Everything?, published in the PLANÈTE AVENIR collection by Five Minutes. Accessible to citizens, professionals, and decision-makers alike, the book examines both the promises of photovoltaics and their technical, economic, and social constraints, without reducing the debate to a simple opposition between optimism and pessimism.

Discover Will Solar Energy Be Enough to Power Everything ? by Léwis Verdun now from FIVE MINUTES and deepen your understanding of the future of solar energy.