Electric cars are a reality, but we don't see models that have some type of solar cells on them to help charge the battery. And the reason is very simple: today solar cells are still inefficient and of the 100 watts of light they receive, they barely generate 15 or 20 watts of electricity.
But even though that's not enough, I don't think it's negligible. Well, if a car is in the sun for many hours, it could generate a few hundred watts that will help it travel additional distance, and all this without costing anything.
On the other hand, the cost of solar panels is relatively expensive, and much more so for panels that are flexible and can be adapted to the geometry of a car roof.
Another problem is the weight. Electric cars are heavier due to the weight of the battery, and adding additional weight works against increasing their range.
And another drawback is that on days when the sun does not shine, the battery does not charge, and in northern countries that happens quite often.
Toyota made an attempt to offer solar panels that were placed on the roof of its Prius model for a price of $600, but that option was not successful and was discontinued. Maybe it was done ahead of time, I don't know.
In recent years, there have been some advances in the development of electric cars with solar cells. For example, the Dutch manufacturer Lightyear launched the Lightyear 0 in 2022, an electric car that with almost 5 square meters of solar panels offered 70 km a day with those solar cells, and announced a range of more than 700 km.
The price was exorbitant, around 250,000 euros, and I don't think they sold many. The company still has a WEBSITE but I do not know what economic conditions it is in.
These advances indicate that electric cars with solar cells are getting closer to becoming a commercial reality. However, some challenges still need to be overcome before this technology becomes widespread.
As time has passed, solar cells have continued to lower their prices and increase their efficiency, which is now close to 30%, and rising. And in addition, flexible solar cells (adaptable to non-flat surfaces) also reduce their prices.
It would not be surprising if in a few years we begin to see that some manufacturers offer the option of including solar cells in some of their electric car models, to increase their autonomy and make them less dependent on charging points.
I like the idea, and I have seen some projections from supposed “experts” that indicate that by 2030 most electric cars will have a solar roof. I doubt it, although I recognize that it would be a good thing.
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