Taiwan Cement has just commissioned a 107MWh energy storage project at its Yingde plant in Guangdong province, China. Subsidiary NHOA Energy worked on the installation and has been promoting it this week. The battery storage works in conjunction with a 42MW waste heat recovery (WHR) unit, a 8MWp solar photovoltaic unit and a proprietary energy management system. It is expected to store about 46,000MWh/yr of electricity and save just under US$3m/yr in electricity costs.
NHOA Energy, formerly known as Engie EPS before Taiwan Cement bought a majority stake in it, claims it is one of the largest industrial microgrids in the world. We can’t verify this for sure, but it is definitely large. For comparison, the 750MW Vistra Moss Landing Energy Storage Facility in California often gets cited as the largest such facility in the world. This is run by a power company, as are many other large battery energy storage systems. In its annual report for 2022 Taiwan Cement said it was planning to using NHOA’s technology to build seven other large-scale energy storage projects at sites in Taiwan including its integrated Suao, Ho-Ping and Hualien cement plants.
The aim here appears to be supplying renewable electricity to the national grid in Taiwan. Taiwan Cement is diversifying away from cement production, with an aim to derive over 50% of its revenues from other activities besides cement by 2025. In 2022 cement and concrete represented 68% of its sales, while its electricity and energy division, including power supply and rechargeable lithium-ion batteries, represented 29%. The company is also not using its own batteries at the Yingde plant. Instead it is using lithium iron phosphate batteries supplied by Ningde Times. This is worth noting, as the cement producer’s batteries are used in vehicles.
Global Cement regularly reports news stories on cement plants that are building photovoltaic solar power arrays. However, so far at least, energy storage projects at scale have been rarer. One earlier example of an energy storage system loosely associated with a cement plant includes the now decommissioned Tehachapi Energy Storage Project that was situated next to the Tehachapi cement plant in California. That project tested using lithium ion batteries to improve grid performance and integrate intermittent generation from nearby wind farms. It is also worth noting that Sumitomo Osaka Cement’s sister company Sumitomo Electric is one of the world’s larger manufacturers of flow batteries, although no installation at a cement plant appears to have happened yet. In simple terms, flow batteries are an alternative to lithium ion batteries that don’t store as much energy but last longer.
More recently, Lucky Cement in Pakistan started commercial operation of a 34MW solar power plant with a 5.59MWh energy storage unit at its Pezu plant in Khyber Pakhtunkhwa in late 2022. Reon Energy provided the equipment including a lithium-ion based battery approach to the storage. Then, in March 2023, Holcim US said that it was working with TotalEnergies to build solar power capacity and a battery energy storage unit at the Florence cement plant in Colorado. TotalEnergies will install, maintain and operate a 33MW DC ground-mounted solar array and a 38.5MWh battery energy storage system at the site. Operation of the renewable energy system is expected to start in 2025.
Away from electrical batteries, the other approach to energy storage at cement plants that has received attention recently from several quite different companies has been thermal batteries. The two prominent groups using them at different scales are Rondo Energy and Synhelion. The former company has developed its Heat Battery technology, which uses refractory bricks to absorb intermittent renewable energy and then supply the energy back as a steady stream of hot gas for use in a cement plant mill, dryer, calciner or kiln. Both Siam Cement Group (SCG) and Titan Cement have invested in Rondo Energy. In July 2023 SCG and Rondo Energy said that they were planning to expand the production capacity of a heat battery storage unit at a SCG plant to 90GWh/yr. Synhelion, meanwhile, has been working with Cemex on using concentrated solar power to manufacture clinker. It achieved this on an ‘industrially viable scale’ in August 2023. It has since been reported that the companies are working on building a small scale industrial plant at Móstoles near Madrid by 2026. Crucially for this discussion though, the process also uses a thermal energy storage unit filled with ceramic refractory material to allow thermal energy to be released at night, and thus ensure continuous operation.
The examples above demonstrate that some cement companies are actively testing out storing energy at scale. Whilst this will not solve the cement sector’s process emissions, it does potentially start to make using renewable energy sources more reliable and reduce the variable costs of renewable power. Whether it catches on remains to be seen. Most of these kinds of projects have been run by power companies and that is where it may stay. It is instructive to note that Reon Energy was the only company to state that its battery-based energy storage system has a life-span of 8 - 12 years. Our current vision of a net-zero future points to high electrical usage but it may be shaped by how good the batteries are… from our phones to our cars to our cement plants.
For more information on Rondo Energy read the January 2023 issue of Global Cement Magazine