SolarPowerNerd
Solar energy and fossil fuels each have real strengths, but neither wins in every category. This article breaks down the key differences in cost, efficiency, reliability, and environmental impact so you can see where each one pulls ahead.
Energy Density
Energy density is a measure of the amount of energy that can be extracted from a particular source on each square meter.
This is not a perfect comparison, because the energy sources are so different from each other that the calculations are not directly comparable, but, regardless of how they are measured, fossil fuels have an energy density much higher than solar energy.
This is one of the reasons why you don’t see solar panels that power too many cars: gasoline provides much more energy than a car’s solar panels can.
Reliability
Coal, natural gas and oil are all examples of fossil fuels with an energy density much higher than that of solar energy.
However, all of these three forms of fossil fuels need to be extracted or exploited from the ground. This is a dangerous and often expensive ordeal.
But once the fossil fuel has been extracted and delivered, it can be used at any time.
For example, you can drive your car at 3:00 am, or bake a cake at midnight.
Solar energy is only available when the sun is shining.
Short winter days, cloudy weather and simple sunrises and sunsets limit the availability of solar energy.
To make solar energy available at other times, you need a way to store energy. Storage solutions are currently available but at a significant price.
If you are exploring battery options, check out our guide to the best solar storage batteries.
Long-term Availability
Solar energy is a form of renewable energy. In other words, as long as the sun exists, we will not lack the light to power our homes, cars and other goods.
Fossil fuels, on the other hand, are non-renewable resources.
Once we run out of the Earth’s fossil fuel reserves, that’s all we have. They will recover technically, but it will take millions of years to do so.
By then, it will be too late to use them.
There’s also the question of access.
We could very well face a future in which the only fossil fuels left to extract from the Earth are in inaccessible places or so expensive that they no longer deserve to be exploited.
In any case, at some point, fossil fuels will no longer be a viable energy option.
Different than fossil fuels, solar energy will be a viable energy option as long as we have access to direct sunlight.
While fossil fuels disappear for millions of years, the sun should remain there all the time.
And as solar photovoltaic technology continues to improve, our ability to capture sunlight and use it as a source of energy will continue to improve.
Emissions
We are all aware that fossil fuels produce carbon dioxide (CO2) as a by-product.
This CO2 is trapped in the atmosphere where it causes the Earth to retain more heat.
This heat retention ultimately leads to phenomena known as climate change that will change both the typical weather patterns observed around the world and make them more sudden and severe.
Climate scientists have long been aware of these problems and people are slowly starting to take an interest in them.
Different than fossil fuels, solar panels don’t produce carbon dioxide or air pollutants.
Their effect on the environment is also very minimal.
All this, according to the U.S. Energy Information Administration (EIA).
Cost
Believe it or not, the cost of solar energy and the absence of CO2 emissions from solar panels are closely linked.
From an environmental standpoint, solar energy is a resource that is more optimal than fossil fuels. For application reliability, coal and natural gas have the advantage.
The best way to compare solar energy with fossil fuels is to compare costs, where solar energy has quickly reached its non-renewable counterparts.
Solar energy still has a long way to go before it becomes the most popular renewable resource on the planet, not to mention the most popular energy resource, but its growing popularity is undeniable.
This is because more and more people want to reduce their carbon footprint and this desire is pushing the solar energy industry to innovate and improve.
Thanks to these technological innovations, the cost of solar energy has fallen by 73% in the last 10 years.
According to the Office for Energy and Renewable Energy (EERE.), the cost of solar energy has decreased every year in these 10 years without exception.
So, although solar energy is not accessible to all individuals and homes today, it is rapidly becoming more and more accessible.
On the other hand, fossil fuels can be expected to become more and more expensive as their reserves run out and their exploitation becomes more and more expensive.
Efficiency
Since 2017, solar panels have been able to convert sunlight into electricity with an efficiency of between 15 and 22%.
At first, it doesn’t look very good, but it has to be considered in the context of other energy sources.
According to Forbes, car engines convert 20% of a car’s petrol into energy.
The rest becomes a waste of thermal energy. What happens with the remaining 80% of unused sunlight?
It illuminates everything it touches.
Coal has an efficiency of 33%-40%, but unlike solar energy, it is a nightmare for the environment.
The fact is that solar energy is not as efficient as it will ever be, but it is improving. Solar panels are much more efficient today than they were in the past.
One of the reasons why the cost of solar energy will continue to decrease is the continuous improvement of the efficiency of the panels.
And the energy that doesn’t turn into electricity does the same thing it would have done without solar panels.
It emits light and heat. It does not pollute our air and does not create excessive heat like fossil fuel engines.
Profitability
Yes, you can make money with solar energy! Once you have installed your solar panels on your home, you will eventually compensate your investment with the amount of money you will save on your electricity bill.
You’ll save money, and in some states you can even sell the excess energy that you produce.
Houses are worth more with solar panels.
Studies have shown that, on average, people are willing to pay an additional $15,000 for a house with a solar system on the roof.
Adding solar energy to your home increases the value of your property, and in some states, you will not see the increase in property taxes as a result of this change.
With fossil fuels, the money you spend tends to never stop.
Advantages and Disadvantages of Fossil Fuels Against Solar Power
The list of advantages and disadvantages of solar energy compared to fossil fuels will probably not surprise you.
Fossil fuels have the advantage of being a reliable resource with almost constant availability.
If you want to take a drive at 3 in the morning or at 3 in the afternoon, there is nothing else to consider as a consumer but a full tank of gas.
However, many people are already aware of the damage caused by oil, gas and coal. This includes intense contamination and also that it’s not an infinite resource.
The full list of “counter” fossil fuels is quite well understood, with one exception: the costs and disadvantages of building your own production facilities.
In short, the operating costs associated with fossil fuel production far outweigh the operating costs associated with solar energy production.
Solar is easily installed on a roof surface or on the ground and uses an already available resource (sunlight).
In comparison, the use of fossil fuels requires soil degradation as a means of producing fuel.
Many people do not know that fossil fuels not only produce greenhouse gas emissions. The drilling process also degrades and erodes the soil and pollutes the water supply.
If you are weighing whether panels make sense for your home, our breakdown on when solar panels are worth it can help.
Comparing Fuel to Technology: Why the Difference Matters
The advantages of solar energy over fossil fuels offer a long list of reasons that homeowners and commercial property owners need to consider.
Yet similar to fossil fuels, solar energy has both advantages and disadvantages.
On the positive side, the reality of solar energy as a green and non-polluting energy source is a great advantage for any source of mass-energy that will be produced on a large scale.
In addition, renewable resources are ideal because they are renewable and not scarce, which can create conflicts, cause price volatility or even lead to war.
This aspect of solar energy is obvious, but the fact that photovoltaics is a technology, and not a fuel, is not.
While fuels are material goods and must be produced, processed and transported, solar photovoltaics is a technological innovation that transforms sunlight into energy at a very efficient rate.
That’s why people are so enthusiastic about solar energy as an energy solution: fuels have a ceiling of innovation, while technologies are constantly improving over time.
You might be aware of Moore’s law that computing power doubles every year, which means that technological innovation will take place at an exponential rate over time.
In return, the costs of this same technology will decrease exponentially over time.
A version of Moore’s law can also be applied to solar energy, as demonstrated by the growth of the photovoltaic “hockey stick” that has occurred in the last decade with falling prices.
The real enthusiasm lies in the potential of solar energy. It is already equivalent to the cost of fossil fuels without subsidies, and there is still room for cost reduction through improved energy efficiency.
The same principle cannot simply apply to a fuel that has to be burned. The natural chemical process of a burned resource cannot “innovate” over time.
Like whale oil before it, the value proposition of today’s fossil fuels peaked a few decades ago.
This does not mean that the global economy will no longer depend on them tomorrow, but with the continuous and dramatic improvement of renewable energy technology, the end of fossil fuels is approaching.
The only real “drawback” of solar energy is that it is not yet accessible to everyone.
Today, not all types of roofs are ideal for solar energy and the amortization period is not short enough to attract all income categories.
Solar energy storage solutions need to be improved so that it can become an energy option accessible to all homeowners, 24 hours a day. Outdoor applications like solar garden lights already show how far the technology has come for everyday use.
And although existing policies already make solar energy an intelligent and profitable investment today, technology must continue its search for ever lower costs to win the battle of tomorrow.
Fortunately, the solar industry is already overcoming these obstacles through advanced research and development to improve photovoltaic equipment, as well as the smarter use of software to easily bring buyers and sellers closer.
For those who are curious about the cost of a solar system, this solar calculator can offer you a customized quote based on your roof and local quotations in your area.
Frequently Asked Questions
Is solar energy more efficient than fossil fuels?
Solar panels currently convert 15 to 22 percent of sunlight into electricity, while coal plants operate at about 33 to 40 percent efficiency. However, car engines only convert roughly 20 percent of gasoline into motion.
Solar efficiency continues to climb each year, and the gap keeps narrowing.
Can solar energy fully replace fossil fuels?
Solar energy alone cannot replace fossil fuels overnight because it depends on sunlight availability. Pairing panels with battery storage and other renewables brings us closer to that goal.
Grid-scale storage projects and policy incentives are accelerating the transition every year.
Why are fossil fuels still used if solar is cheaper?
Existing infrastructure for coal, oil, and natural gas represents decades of investment that cannot be replaced instantly. Fossil fuels also provide on-demand power regardless of weather or time of day.
As solar costs continue to fall and storage improves, the economic case for fossil fuels weakens steadily.
How long do solar panels last compared to a fossil fuel plant?
Most solar panels carry warranties of 25 to 30 years, and many continue producing electricity well beyond that. A typical coal or natural gas plant has a similar operational lifespan but requires ongoing fuel purchases.
Solar panels need very little maintenance once installed, which keeps long-term costs low.
Final Thoughts
Solar energy is outperforming fossil fuels on cost, emissions, and long-term availability, and the gap keeps widening. As panel efficiency improves and storage technology advances, solar is becoming accessible to more homeowners and businesses every year.
Fossil fuels still dominate energy markets today, but their reserves are finite and their environmental costs are rising. By investing in solar and participating in renewable energy programs, individuals and businesses can help speed up the transition to cleaner, more sustainable power.
