In this guide, we list the pros and cons of solar energy.
This guide forms part of a series of guides we have put together outlining the benefits and disadvantages of different energy sources and energy generation methods.
Summary – Pros & Cons Of Solar Energy
– Solar is renewable (not finite like fossil fuels or potentially uranium)
– There is no re-fuelling that needs to take place once solar panels are set up (unlike coal plants for example)
– Is a portable form of energy
– Can be used for small applications as well as larger applications
– Can be used off grid
– Can give people energy independence in some ways
– Technology has been improving to increase capabilities
– Demand is increasing, which has been dropping prices to manufacture and also buy in some places
– Solar electricity prices for consumers can be more stable than fossil fuel electricity prices in some places and some instances
– Solar requires fairly simple maintenance once up and running compared to nuclear for example (generally cleaning of the panel is all that is required for most smaller units)
– Setup costs can generally be recovered over the life of solar panels
– The typical solar panel has a reasonable lifespan of around 20 to 25 years
– Solar has the benefit of setting up as many or as little panels as you like – it’s easy to set up in stages or in increments to your preferences or needs … compared to a nuclear plant or a coal plant, where you have to build and set up a whole plant over say 6 to 8 years
– Large scale solar is usually distributed across a wide geographical area, and modular, with several individual panel or panel farms.
This creates less chance of damage to equipment or disruption to electricity supply in the case of extreme weather or a natural event in one area, compared to a fossil fuel plant that has one power plant in one spot
– Land used for solar panels can be multi use i.e. sometimes solar panels and wind turbines are installed on the same land together (so, renewables like solar might have better land use efficiency than some think)
– Solar can be set up on buildings – both residential and commercial
– Low power output per unit (low power density) compared to nuclear, oil, gas
– Not suited right now to be the primary or sole energy source for large cities for a few reasons
– Transitioning to solar can have challenges for some countries and cities
– Price per kilowatt can be expensive in some countries, and renewables have been linked to higher electricity prices in some countries.
Also, the setup of many panels can be expensive (but prices are dropping with tech advancements and economies of scale)
– Return on investment can take time
– Needs lots of space/land the more panels you add, unless you are installing them on buildings
– Solar energy can be variable/intermittent
– Relies on batteries for energy storage
– Not suited to places with little sun
– Solar panels can require scarce materials to make
– Oil is usually used to make some solar products
– Fossil fuels and plastic are used to make some types of solar panels
Solar can be a good option for individuals and households at the moment as long as it makes sense financially for them.
But, with current solar technology, solar isn’t as suited to large scale consistent power supply for cities in some ways as say fossil fuels or nuclear might be.
Technological advances will hopefully change that in the future, as well as our ability to integrate solar power better into a city’s power supply.
At the moment, solar is more of a supplementary power source for the cities that use it, and isn’t as much of a primary source (but, that is changing as capabilities and technology change)
As long as costs are competitive, and technology keeps advancing to increase power density/power output per unit, solar probably has a good long term outlook (along with wind energy)
There has been and might continue to be more financial investment into solar
*Note – the above pros and cons are broad generalisations.
Obviously there are different variables to each specific energy project that impact the final pros and cons (like new technology that reduces emissions for coal power plants just as one of many examples).
Each energy project and situation (in different countries and cities) should be analysed individually.
Having said that, some broad principles and patterns about the pros and cons of different energy sources tend to stay consistent too.
Pros Of Solar Energy
Is Renewable & Sustainable
Not finite like fossil fuels such as coal, oil, and gas.
Even nuclear may run out in the next 80 years when uranium is in low supplies.
Solar energy from the Sun is expected to be available for the next 5 billion years – which is how long the Sun is expected to last
Is Clean & Carbon Emission Free While In Operation
Produces no carbon dioxide or other greenhouse gases while in use, unlike fossil fuels such as coal, oil, and gas.
GHGs are produced in manufacturing solar panels, but these are seen to be negligible when compared to the GHGs emitted by other energy sources.
Solar energy also doesn’t produce waste while in operation, whereas coal for example produces fly ash and other waste
Fuel Is Free, & No Refuelling Is Required
Once a solar panel is set up, there is no refuelling process that needs to take place unlike a coal power plant for example
Additionally, solar energy is free, unlike coal that needs to be purchased.
Can Be Used Off The Grid, & Gives Energy Independence
Solar power doesn’t always require access to a power grid, so it can generate electricity anywhere panels can be installed, even low income or less developed countries.
It can be used by people free of utility companies.
Technology Is Improving
Better technology means more efficiency (and other benefits)
Companies and countries like Tesla are also working on storing excess solar energy in a cheaper way, whilst Germany has put money into solar as well
Quantum physics research and advancements in nanotech also have the potential to greatly increase the power output of solar panels, which could lead to wider-scale use of them across the globe
Demand Is Increasing, & Prices Are Dropping In Some Places
Companies are working to make it more affordable, and higher demand means prices come down to both produce solar energy equipment, and purchase solar power naturally.
Countries like China are heavily investing in installed capacity of renewable energy like solar
Electricity Price Stability In Some Places
Fossil fuel prices can fluctuate in response to world fossil fuel events and the market in some places.
Renewable energy can be much more stable in some places because of stable operating costs (ucsusa.org)
Portable, Versatile & Can Be Used For Unique Applications
Can be used to power a range of products and devices small and large, from cars down to mobile phones.
Portable solar power panels and chargers are also available.
More solar energy uses are coming out as time progresses – making solar versatile.
Compared to energy like nuclear for example.
Residential solar panels for example require cleaning once, maybe twice per year.
Reasonable Life Span
The typical solar panel set up lifespan residentially is around 20-25 years (in comparison – some nuclear reactors around the world can last 40 years, or up to 60 years if they undergo lifetime extension work)
The typical manufacturer’s warranty lasts anywhere from 20 to 25 years.
Distribution & Modular Set Up
Solar is usually distributed across a wide geographical area, and is modular with several individual panels or panel farms.
This creates less chance of damage to equipment or disruption to electricity supply in the case of extreme weather or a natural event in one area, compared to a fossil fuel plant that has one power plant in one spot.
Hurricane Sandy had this impact (power loss and damage) on fossil fuel plants in New York and New Jersey, but not as much on renewable energy projects (ucsusa.org)
– renewableresourcescoalition.org, ucsusa.org
Cons Of Solar Energy
Low Energy Density & Power Output
Compared to nuclear, oil, and gas, solar has a much lower power output per unit.
Solar is unable right now to provide sufficient energy to power something like a large manufacturing plant with lots of big machinery as one example
Right Now, It’s Not Suitable For Some Cities As The Predominant Or Sole Energy Source On Large Scale Power Supply
Solar isn’t as good to scale for some large cities and countries right now as other energy sources.
The power output is not there, and existing power infrastructure isn’t built around it – meaning captured solar energy is lost from the installed capacity that could otherwise get fed into the grid (China is an example where captured solar energy is lost in transfer to the grid).
Can Be Expensive & Can Lead To Higher Electricity Prices
Compared to other alternative energies, the price per kilowatt can be expensive, and some nuclear reactors around the world can last 40 years, or up to 60 years if they undergo lifetime extension work.
Also, upfront costs can be expensive (household panels can be $1000’s of dollars).
But, costs are gradually dropping in some places
Return On Investment Can Take Time
Residentially, a homeowner needs to look at the number of years it takes to recoup their initial and ongoing costs.
It could be a number of years in some instances.
Some of this depends on credits and incentives given to solar users though.
Needs A lot Of Space, & Has A Lower Power To Space Ratio
Solar panel farms usually need a lot of space and land to be laid out compared to other forms of energy.
The mean power density for solar is about 170 W/m2, much more than other renewable energy sources, but nowhere near the amounts of energy sources such as nuclear.
It struggles to compete against alternative energy sources based on its low power density (space to power output ratio).
As technology gets better, smaller panels may produce more power per square metre.
Depends On The Sun & Can Be A Variable/Intermittent Power Source
Relies on exposure to, and the intensity of the sun.
If the sun is not out like at night time or on overcast days or in colder climates, you’re limited in the energy you can use (although solar CSP panels can change this somewhat, as well as newer solar panels being developed)
This wouldn’t be as much of an issue if there was a cheaper way to store excess solar energy.
Intermittent energy isn’t a problem for energy sources like nuclear or fossil fuels.
Relies On Batteries For Energy Storage
Solar and wind as variable energy sources require batteries to store and use energy later on.
For larger scale power production, these batteries can be energy intensive to make, and are obviously expensive.
There’s also the issue of recycling batteries or disposing of them (electric vehicles will have this issue to address in the future too)
Batteries might also require the use of precious metals to make
Solar Panel Cells Require Rare Materials
Cadmium telluride and copper indium gallium selenide are examples that are not as easily found on earth as coal and fossil fuels.
Solar Requires More Construction Material Than Nuclear
Solar requires 18 times, and wind 11 times, the construction materials of nuclear.
Along with more construction materials, comes a bigger waste footprint, and an associated environmental footprint too
There’s also resource management sustainability question that might arise from this use of materials
Might Not Be As Emission Friendly As Nuclear
Solar power produces four times more GHGs than nuclear in total (dailymaverick.co.za)
Oil Is Usually Used To Make Some Solar Products
Such as PV panels.
Oil comes from fossil fuels.
However, some companies are now offering ‘Bio’ solar panels that don’t use oil
Fossil fuels and plastic are used to make some types of solar panels
The energy used to make solar panels in many cases comes from fossil fuels like coal.
Additionally, plastic is used in the construction of solar panels, and plastics come from fossil fuels as well.
Although, there are new solar panels coming onto the market that try to steer away from virgin plastic use (via recycling plastic), or steer away from plastic altogether.
– renewableresourcescoalition.org, bettermeetsreality.com, dailymaverick.co.za