Ofgem is a British government watchdog for energy. It does not sell you gas or electricity. It watches the firms that do, and the pipes and wires that carry the power, mainly in Great Britain. Its job is to keep that market working, to stop unfair prices, and to see that the system is run properly. The name is a squeeze of Office of Gas and Electricity Markets; almost nobody says the long form. You hear Ofgem in UK news when bills jump, when a supplier collapses, or when the rules for the grid change. Households in Taiwan will never deal with it — it is a UK institution, a specialised referee. Northern Ireland has a separate energy regulator, so “British” in headlines is a little looser than “the whole United Kingdom.” People often grumble as if Ofgem could simply order world gas prices down. Its real power is over market rules, not over the weather or a war that sends fuel costs soaring.

英國天然氣與電力市場辦公室（能源業的政府監管機關；通常直接叫 Ofgem）