CleanSpark (NASDAQ:CLSK) CEO Zach Bradford on Wednesday evening said his company has been considering "strategic alternatives" for the energy business, an emerging eco-friendly sector within the cryptocurrency mining space. Meanwhile, shares of CLSK climb about 6% in premarket trading, as bitcoin (BTC-USD -0.2%) flirts with $45K per token. As part of its ambition to become a top five publicly traded miner in terms of its commitment to sustainability, "we have engaged NASDAQ’s ESG advisory services to analyze their performance and help us engineer a roadmap for achieving our success," Bradford said during the Q4 earnings call. Recall first-quarter energy hardware, software and services revenue were $3.97M, up from $1.21M in the year-ago quarter. Previously, (Feb. 3) CleanSpark's bitcoin production rose to 305 in January.