While renewables and storage are transforming the energy landscape, deeper decarbonization calls for new tools
By Pinky Thomas
As the impacts of climate change intensify globally, the urgency to reduce greenhouse gas (GHG) emissions has never been clearer. Scientists and policymakers agree that immediate and sustained action is essential to limit global temperature rise and prevent the most severe consequences of climate disruption.
The Paris Agreement, adopted in 2015, sets a goal to limit global warming to well below 2°C, with an aspirational target of 1.5°C above pre-industrial levels. It calls for global greenhouse gas emissions to peak as soon as possible and reach net-zero around 2050.
For the United States, this translates into an updated nationally determined contribution (NDC) target set in 2024 to reduce net greenhouse gas emissions by 61–66% below 2005 levels by 2035, a shift from the previous 50–52% goal. This range aligns with a straight-line or steeper path toward achieving net-zero emissions across all greenhouse gases by 2050. To meet this ambitious target, emissions must decline by roughly 7.6% annually from 2025 onward, necessitating deep decarbonization across multiple sectors, particularly energy.
READ: Costa Rica step towards creating a society without fossil fuels (August 21, 2016)
The energy sector, responsible for the largest share of emissions, is central to this effort. In 2024, the U.S. experienced a surge in electricity demand, mirroring the global trend. This increase was primarily driven by record-high temperatures that raised cooling needs, alongside growing industrial activity, transportation electrification, and the energy demands of expanding data centers. During this same year, solar and wind generation collectively surpassed coal for the first time. Despite these gains, U.S. greenhouse gas emissions decreased by just 0.2% in 2024, according to a preliminary estimate by the Rhodium Group. This marginal decline highlights how the U.S. — the world’s largest economy — is off track to meet its climate goals.
Reducing greenhouse gas emissions at scale requires rapidly decarbonizing electricity. The most effective way to achieve this is by replacing fossil-fueled generation with renewable energy sources. The key renewable technologies leading this transition include solar power, wind power (both onshore and offshore), hydropower, geothermal energy, and biomass or bioenergy. Among these, solar and wind have emerged as dominant forces in new power generation capacity globally and in the U.S.
Renewables offer a range of benefits in the fight against climate change. They have a low carbon footprint, emitting little to no greenhouse gases during operation. They rely on abundant and domestic resources—sunlight and wind are widely available and free. From an economic standpoint, renewables are increasingly cost-competitive.
IRENA reports that in 2023, utility-scale solar and onshore wind were the cheapest sources of new electricity generation in the U.S., even without subsidies, based on the Levelized Cost of Electricity (LCOE) analysis.
Additionally, the clean energy sector is a powerful driver of job creation. U.S. Department of Energy reports that in 2023, clean energy jobs in the U.S. grew by 4.9%, more than twice the rate of the broader labor market, adding 149,000 new jobs, partly due to federal investment through the Inflation Reduction Act (IRA).
The energy landscape is shifting. Fossil fuel power plants, particularly coal-fired ones, are retiring at a record pace. New installations are dominated by solar and wind projects. Wind and solar accounted for 14% of U.S. electricity generation in 2022. According to the U.S. Energy Information Administration’s February 2024 Short-Term Energy Outlook, this share rose to 16% in 2023 and is projected to reach 18% in 2024. This transition is critical, especially considering that electricity production in the U.S. accounted for 1,539 million tonnes of CO₂ emissions in 2022.
However, renewables also face several challenges. One of the biggest is that the amount of electricity solar panels and wind turbines produce isn’t consistent throughout the day or across seasons. It all depends on the weather—cloudy days mean less solar generation, and calm weather with little wind leads to a dip in wind power output. This variability makes it tricky to always match electricity supply with demand. To effectively use these clean energy sources, we also need to upgrade our electric grid to be smarter and more flexible.
On top of that, large solar and wind farms require space and need to be carefully placed so they don’t negatively affect local communities or ecosystems. Even with these challenges, strong policies, continued investments in grid upgrades, and advances in technology are putting renewables in a strong position to lead us toward a carbon-free energy future.
This is where energy storage steps in. Since solar and wind output changes based on natural factors—like when the sun sets or the wind dies down—we need a reliable way to store extra electricity when it’s available and use it later when it’s not.
Today, technologies like lithium-ion batteries, flow batteries, pumped hydro, and even thermal storage help store electricity during times of high renewable generation—like sunny afternoons or windy nights. That energy can then be used in the evening or during calm weather when renewable output dips. These systems help balance the flow of electricity, keeping the lights on no matter the weather.
Energy storage does more than just save power for later. It helps maintain the delicate balance between how much electricity is being generated and how much is being used. It also provides a backup when there’s a disruption in supply and reduces our need to rely on fossil fuel-based power plants that can be expensive and polluting to run. In short, storage strengthens the backbone of the clean energy system.
READ: CO2 reduction possible only by controlling industries and capping fossil fuel emissions (June 21, 2016)
ERCOT’s RTC+B Initiative
ERCOT, Texas’s grid operator, is piloting Real-Time Co-Optimization + Battery (RTC+B)—a market enhancement designed to better integrate energy storage into real-time operations while enabling the co-dispatch of energy and ancillary services. RTC+B allows batteries to contribute based on their state of charge, with ERCOT’s SCED system automatically selecting the most efficient combination of resources. If needed, the system reassigns other assets—including generators, batteries, or demand-side resources—to maintain ancillary service requirements. This initiative boosts grid flexibility, supports renewable integration, and strengthens reliability—offering a blueprint for other states advancing toward clean energy.
With technology costs falling, supportive policies in place, and a growing emphasis on innovation, energy storage is poised to become the backbone of a decarbonized electricity system. Combined with renewables, it enables a more flexible and reliable grid capable of meeting demand while cutting emissions. This transformation lays the foundation for a net-zero energy future.
Up next: Innovative carbon reduction strategies
While renewables and storage are transforming the energy landscape, deeper decarbonization calls for new tools. In the next article, we’ll explore the growing role of carbon capture, utilization, and storage (CCUS), direct air capture (DAC), and the potential of carbon-negative technologies. We’ll also take a closer look at alternative fuels such as electrofuels (eFuels), green hydrogen, and bioenergy, which are essential for reducing emissions in hard-to-abate sectors like aviation, shipping, and heavy manufacturing.