Due to the depletion of fossil fuels, biofuel production from renewable sources has gained interest. Malaysia, as a tropical country with huge resources, has a high potential to produce different types of biofuels from renewable sources. In Malaysia, biofuels can be produced from various sources, such as lignocellulosic biomass, palm oil residues, and municipal wastes. Besides, biofuels are divided into two main categories, called liquid (bioethanol and biodiesel) and gaseous (biohydrogen and biogas). Malaysia agreed to reduce its greenhouse gas (GHG) emissions by 45% by 2030 as they signed the Paris agreement in 2016. Therefore, we reviewed the status and potential of Malaysia as one of the main biofuel producers in the world in recent years. The role of government and existing policies have been discussed to analyze the outlook of the biofuel industries in Malaysia.

Nowadays, electricity consumption has increased worldwide due to the activity of cryptocurrency miners. Much of Iran’s electricity is generated by fossil fuel power plants. So, generating more electricity means producing more air pollutants in Iran. There is not sufficient information about the effects of cryptocurrency mining on Iran’s air pollution. This study aims to estimate the amount of carbon monoxide (CO), sulfur oxides (SO_x), nitrogen oxides (NO_x), volatile organic compounds (VOCs), and particulate matter (PM) emitted by Iran’s power plants when they generate extra electricity for cryptocurrency miners. In this study, we firstly estimated the amount of fuel used for the electricity needed for cryptocurrency miners. Then, the amounts of emitted NO_x, CO, VOCs, SO_x, and total PM for generation of such electricity were estimated via the guidelines of the European Environment Agency for emission inventory estimation. The results showed that an on average of 3530, 1547, 103, 11, and 35 tons of NO_x, CO, VOCs, SO_x, and total PM, respectively, have been emitted into the atmosphere in Iran annually.