Every square meter of uncovered parking in a city is a wasted opportunity.
As asphalt overheats, cars cook in the sun, and cities are transformed into urban ovens, a silent solution is beginning to gain ground in the world.
Solar canopies, those structures that cover parking lots with photovoltaic panels, promise to cool cities, protect vehicles and generate clean electricity, all at the same time and without taking up additional land.
Making the most of every urban inch in Smart Cities
By: Gabriel E. Levy B.
Imagine arriving at the mall on a Saturday at noon.
The thermometer reads 34 degrees, the asphalt of the parking lot shines like a red-hot iron and his car, parked there for three hours, receives him with a blow of hot air that seems to have come out of an oven.
The scene is repeated every day in thousands of cities around the world, from Cali to Phoenix, passing through Madrid, Buenos Aires and Singapore.
The curious thing is that on those same square meters of overheated cement a small power plant capable of feeding entire neighborhoods could be operating.
The idea is not new, but it is experiencing a golden moment.
They are called solar pergolas, photovoltaic canopies or, in the most technical vocabulary, “solar carports”.
They are raised metal structures that cover the uncovered parking spaces and have solar panels on their roof. They solve several problems at the same time and that is why they have slipped into the list of priorities of those who think about the smart cities of the future.
Three problems, one solution
When a city planner looks at an outdoor parking lot, he basically sees a waste.
Hectares of paved surface that only serve one function during the day and that, in addition, contribute to heating the city.
The phenomenon has a technical name: urban heat island, and describes that thermal bubble that envelops large cities and makes them several degrees hotter than the surrounding countryside.
Asphalt absorbs solar radiation during the day and returns it to the environment at night, preventing cities from cooling off.
Solar canopies attack this phenomenon from two sides. On the one hand, they generate shade on the ground and drastically reduce the amount of radiation that reaches the pavement.
Studies conducted in Arizona and California show that the temperature beneath these structures can be between seven and ten degrees lower than in an area uncovered in full sun.
On the other hand, the panels absorb some of that energy and convert it into electricity, rather than letting it transform into heat.
Added to that is the comfort for drivers. A car parked in the sun for two hours can reach internal temperatures of 60 degrees or more, which spoils paint, cracks dashboards and causes the air conditioner to work twice as hard as soon as the engine is turned on. Pergolas also protect against rain, hail and pigeon droppings, those little everyday enemies of every motorist.
The miracle of numbers
But the truly shocking thing about this technology appears when you do the math. A medium-sized parking lot, with about 200 spaces, occupies approximately 5,000 square meters. If completely covered with solar panels, it can generate between 1 and 1.5 megawatts of installed power. Translated into everyday language, that is equivalent to the annual electricity consumption of about 400 family homes.
France has already made calculations on a national scale and the results are dizzying. In 2023, the French government passed a law that requires all car parks with more than 80 spaces to be covered with solar panels within three to five years, depending on the size. Official estimates speak of about 11 gigawatts of additional capacity, equivalent to ten medium-sized nuclear reactors. And all this without occupying an additional square meter of natural land, without cutting down trees, without displacing communities, without removing earth. On cement that already existed.
Spain followed a similar path and several autonomous communities offer aggressive tax incentives for companies that install these structures.
In the United States, giants such as Walmart, Costco and Disney have been filling their mega parking lots with solar canopies for years. Tesla’s Fremont factory has one of the most photogenic projects in the world, with thousands of panels covering both employee and visitor parking lots.
How a typical installation works
The technical process is surprisingly simple, at least in concept. First, a metal structure is designed, usually made of galvanized steel, which is anchored to the ground by means of concrete footings. These footings are distributed among the parking spaces, occupying the dead spaces that already existed between vehicles. The clearance is usually between 2.5 and 3 meters, enough for any private vehicle to pass without problems.
A sloping roof is mounted on this structure, almost always oriented towards the south in the northern hemisphere and towards the north in the south, with a slope calculated to capture the maximum radiation throughout the year. On top of them are the photovoltaic panels, connected to each other by wiring that is hidden inside the metal profiles for aesthetic and safety reasons.
The electricity generated goes down through cables to a technical room where the inverters are located, those devices that transform the direct current of the panels into alternating current suitable for the grid. From there, energy can be used in three ways. It can directly feed the building associated with the parking lot, whether it is a shopping center, a factory, a hospital or an office building. It can be sold to the national power grid. Or it can be stored in batteries to be used when the sun is gone.
An increasingly popular combination consists of harnessing part of this energy to power electric vehicle charging points installed in the same spaces. The circle closes elegantly. The sun falls on the roof, fuels the car that is parked underneath and, in the meantime, the driver buys clothes or eats lunch at the mall. Clean mobility, commerce and electricity generation articulated in the same point.
What it costs and what it gives back
The investment is not minor. Filling 200 positions can cost between $800,000 and $1.5 million, depending on the country, the quality of the panels and the complexity of the project. But the return is usually between six and ten years, after which the installation produces electricity practically free for another 20 or 25 years. For a supermarket, a hospital or a university these are numbers that are difficult to ignore.
There are other, less visible benefits. The installation boosts the real estate value of the property, improves the corporate image of the owner company and, in many countries, opens the door to sustainability certifications that weigh in public tenders and tenders. Customers are increasingly valuing indoor parking and, according to consumer behavior studies, they tend to stay longer when they know their car is protected.
Obstacles on the way
Not everything is panel color, of course. Initial investment continues to be a major obstacle for small landowners and municipalities with tight budgets. The bureaucracy for obtaining permits can be labyrinthine, especially in cities without clear regulatory frameworks for this type of infrastructure. In some countries, connection to the electricity grid faces bottlenecks and slow procedures.
There are also aesthetic debates. Not everyone wants to see acres of shiny panels from their home balcony, and some historic cities resist the massive installation of these structures in their heritage areas. Designers are working on more integrated versions, with semi-transparent or coloured panels that blend better into the cityscape.
But the trend seems unstoppable. As climate change tightens and cities desperately look for spaces where they can generate energy without sacrificing land, uncovered parking lots appear to be one of the most obvious and underutilized solutions we have at hand. The next time you park your car in a scorching sun, look up. Perhaps in a few years, above his head, a small silent power plant will be running, while his vehicle rests cool and in the shade.
In short, solar canopies represent one of the smartest bets in contemporary urban planning.
They take advantage of already built areas to generate clean energy, reduce urban heat islands, protect vehicles from the weather and, in many cases, power electric charging points.
Although the initial investment may be high, the economic and environmental returns are solid, and countries such as France and Spain are already leading the way with ambitious regulations.
