The Promise of Solar Power
In an increasingly carbon-constrained world, solar energy technologies represent one of the least carbon-intensive means of electricity generation. According to the United Nations Chronicle, solar power produces no emissions during generation itself, and life-cycle assessments clearly demonstrate that it has a smaller carbon footprint from cradle-to-grave than fossil fuels.
Currently, solar accounts for just a tiny fraction of global electricity generation – a mere 8 terawatt-hours (TWh) out of the over 10,000 TWh produced by the countries of the Organization for Economic Cooperation and Development (OECD). Yet, solar technologies, including photovoltaics (PV), concentrating solar power (CSP), and solar thermal, constitute the fastest-growing energy source in the world. With clear market signals from governments, these low-carbon technologies could provide more than 30% of the world’s energy supply in aggregate by 2040.
As a solar energy solutions provider, we at Solarasystems Inc. are excited about the potential of solar power to help mitigate climate change and create a more sustainable future. In this article, we’ll dive into the details of how solar panels can reduce your carbon footprint and explore the various ways the solar industry is working to make this clean energy source even greener.
The Carbon Footprint of Solar Panels
The International Panel on Climate Change (IPCC) has found that the life-cycle carbon dioxide (CO₂) emissions for photovoltaic (PV) solar systems are now in the range of 25 to 32 grams of CO₂ equivalent per kilowatt-hour (g CO₂e/kWh) of electricity generated. According to Cool Effect, this compares quite favorably to other sources of electricity – a combined-cycle gas-fired power plant emits around 400 g CO₂e/kWh, while a coal-fired power plant with carbon capture and storage emits about 200 g CO₂e/kWh. Even nuclear power, often touted as a low-carbon option, emits 25 g CO₂e/kWh on average in the United States, with only wind power faring better at 11 g CO₂e/kWh.
To put these numbers in perspective, let’s visualize the carbon emissions as medium-sized chicken eggs. One kWh of electricity is roughly what it takes to power a fridge for a day, and the IPCC estimates that generating that 1 kWh from rooftop solar panels results in around 41 grams of CO₂ equivalent emissions – about the mass of a single medium-sized chicken egg.
Now, let’s say you use 15 kWh of electricity per day. That’s the equivalent of 15 eggs’ worth of carbon emissions from your daily electricity consumption. Over the course of four days, you’d have 60 eggs’ worth of emissions piling up in your refrigerator. Yikes!
Of course, carbon emissions aren’t literally eggs, but the analogy helps illustrate just how much cleaner solar power is compared to fossil fuel-based electricity generation. And the good news is that there are even more opportunities to reduce the carbon footprint of solar panels further.
Lowering the Carbon Footprint of Solar
According to the National Renewable Energy Lab, the life-cycle carbon emissions of solar panels can be divided into three main categories: manufacturing, operations, and end-of-life. And at each stage, there are ways to decrease the environmental impact.
Manufacturing Emissions
The carbon footprint of manufacturing solar panels accounts for roughly two-thirds of the life-cycle emissions of solar energy. This includes processes like extracting raw materials, producing equipment, and constructing the manufacturing plants themselves – all of which have historically been powered by fossil fuels.
However, as we transition to renewable energy sources, we can reduce these upstream emissions by using clean energy to create cleaner energy. For example, researchers are exploring ways to upcycle silicon powder waste created during solar panel manufacturing to reduce the need for extracting raw materials and the associated emissions.
Additionally, there are efforts to repurpose existing infrastructure for solar manufacturing, like turning a 118-year-old steel processing plant into a solar torque tube factory. By leveraging these kinds of innovative approaches, the solar industry can lower the carbon footprint of panel production.
Operational Emissions
The operational emissions of solar panels, meaning the carbon footprint once they are installed and generating electricity, are minimal, especially for rooftop systems that require virtually no maintenance or transmission. Even so, the operational emissions per kWh can be further reduced by increasing the solar panels’ efficiency and output.
Fortunately, solar panels are becoming more efficient and lasting longer than expected. In fact, a 40-year-old rooftop solar panel in Vermont is still operating at around 92% of its original output. As the technology continues to improve, the operational carbon footprint of solar will only get smaller.
End-of-Life Emissions
The smallest portion of the carbon footprint of solar panels comes from the downstream emissions of deconstructing and disposing of the systems. But even here, there are opportunities to reduce the environmental impact.
The key is in solar panel recycling, an industry that is poised for rapid growth in this decade. Over 90% of the materials used to make solar panels can be recycled, including the aluminum frame, glass cover, copper wire, silicon wafer, and plastic junction box. By recycling these components, we can not only decrease downstream emissions but also reduce the need for raw materials, thus lowering upstream emissions as well.
The Net Positive Impact of Solar Power
When you consider the life-cycle emissions of solar panels – from manufacturing to operation to end-of-life – the total carbon footprint is around 12 times less than natural gas and 20 times lower than coal for every kWh of electricity generated. And unlike burning fossil fuels, which will always produce harmful emissions, there is tremendous potential to further reduce the carbon footprint of solar power through innovation and improved processes.
In fact, a 2014 report by the IPCC found that the life-cycle emissions of solar PV systems could be reduced to just 15 g CO₂e/kWh within a few years as silicon growth processes become more efficient. That’s less than the emissions from nuclear power and just a fraction of the carbon footprint of traditional fossil fuel-based electricity.
So, while there is certainly a carbon footprint associated with solar panels, the environmental benefits of this clean energy technology are clear. And as the industry continues to evolve, the ability of solar to reduce your personal carbon footprint will only increase.
If you’re ready to take the next step in your sustainability journey, I encourage you to explore solar solutions for your home or business. Not only will you be reducing your carbon footprint, but you’ll also be saving money on your energy bills and contributing to a cleaner, more sustainable future. It’s a win-win-win situation!
