Opec has forecast up to 5,000 scrubber installations by the end of 2023, saying shipowners will increasingly seek to take advantage of wider discounts of high-sulphur fuel oil to 0.5%-sulphur bunker fuel once the IMO 2020 regulations kick in.

In its World Oil Outlook 2018, the oil cartel said the pace of installing exhaust gas cleaning systems would pick up only from next year, shortly before the new bunker rules come into force and financial incentives in the form of such discounts materialise.