Chia, marketed as an eco-friendly alternative to Bitcoin, is facing scrutiny for its energy consumption, which is reported to be 18 times higher than what its developers initially claimed. Chia Network has admitted that this figure is “not far off.”

Unlike Bitcoin, which depends on energy-intensive mining through a proof-of-work system, Chia employs a space-time proof mechanism that doesn’t require massive computations but rather relies on unused hard disk space. Currently, Bitcoin consumes around 157 terawatt-hours annually, roughly equivalent to the energy usage of all of Poland. In contrast, Chia miners earn new coins based on the amount of space they allocate for data and the duration they maintain that allocation.

Getting started with Chia involves two main processes: plotting and farming. Plotting is a CPU and memory-intensive task that generates data for storage, while farming involves simply storing data and confirming its existence to the network. High-speed solid-state drives (SSDs) are typically used for plotting, whereas economical, slower hard drives are used for farming.

A study by Soraya Jerab and her team at Algeria’s High School of Computer Science and Digital Technology revealed that the plotting phase consumes a significant number of SSDs, contributing to Chia’s carbon footprint. Their research involved precise power measurement of devices engaged in various Chia tasks, revealing that Chia’s annual CO2 emissions are likely between 0.584 million and 1.402 million tonnes. This estimate vastly exceeds the claimed 50,000 tonnes, indicating emissions two orders of magnitude larger than other mainstream blockchains like Ethereum.

“The primary emissions are from hardware production,” notes Jerab. “To use Chia, new hardware must be purchased, and this production process consumes energy.”

The researchers found that running the plotting process just 160 times could lead to the rapid degradation of a new SSD, and Chia’s alternative plotting methods might further increase emissions by requiring more RAM and GPUs, which are also energy-intensive.
As co-author Clementine Gritty stated, “While it’s still better than Bitcoin, it won’t save the planet.”

Gene Hoffman, CEO of Chia Network, argues that the study’s findings overstate the network’s environmental impact. “We are being charged for the carbon footprint of building drives that would’ve gone to landfill after four years of use. Chia farming has created a market for otherwise discarded hardware,” he said.

In any case, Hoffman is optimistic about upcoming changes to the Chia network. The anticipated Proof of Space 2.0 is expected to significantly reduce emissions and improve energy efficiency. “We believe we’re doing a good job, and Proof of Space 2.0 will be even more effective,” he asserted.