Could Tesla Megapacks Actually Help Replace Coal Power Plants?

Tesla Megapacks are shipping container-sized battery packs, each capable of storing roughly 3.6 MWh, or 3,576 kWh, of electrical energy. Tesla Megapacks, along with other energy storage solutions including Switzerland's powerful underground battery, can't produce power on their own. The production of electricity still relies primarily on coal and other fossil fuels, hydroelectric, wind, and solar. While hydro, wind, and solar are great examples of renewable electric power, there are some limitations, especially for meeting peak demand.

Hydroelectric power generation is limited by the flow of water, although the operators of hydro plants can adjust to flow to meet demand to a point. Wind and solar can only produce power when conditions are right. Periods of little to no wind render wind turbines motionless, and solar panels don't work at night or when it's cloudy, raining, or snowing, at least not to their full potential.

Adding Tesla Megapacks to the grid provides a way to mitigate shortfalls during peak demand and periods of low production. The electricity they store comes from excess power generated during periods of low demand.

Having enough stored energy could eliminate the need for fossil-fuel powered peaker plants that kick in only during times of short supply. Tesla Megapacks can also fill in the gaps when solar and wind power generation falls short, making the switch from coal to renewable energy sources more realistic.

While they're capable of powering utility-scale projects, it's true that Tesla Megapacks are large-scale batteries that cannot produce electricity on their own. That said, they can store massive amounts of power, helping to offset the need for some fossil fuel-burning plants, including coal.

Queensland, Australia plans to use as many as 324 Tesla Megapack 2XL units to replace its Stanwell coal power plant located near Rockhampton. The 300 mega-watt Stanwell Battery Project will provide 1,200 MW-hours of energy storage. Some estimates put that at enough energy to power nearly 42,000 homes for 24 hours.

Hawaii's Kapolei Energy Storage (KES) installation came online in late 2023, 15 months after Oahu's 30-year-old coal-fired power plant shut down. Hawaii is phasing out its coal-fired power plants with plans to rely 100% on renewable energy sources in the future due to environmental concerns and the passage of a 2020 state law.

KES occupies eight acres of industrial-zoned land with 158 Tesla Megapack 2XL battery packs totaling 565 MWh of energy storage with a discharge rate up to 185 MW. According to Plus Power, KES developer, that's enough for three hours of peak demand for 17 percent of Oahu's electrical grid.