The heat transport capability of the steam generator (SG) in a high-temperature gas-cooled reactor (HTGR) is compared with SGs in other reactor types, for example, in gas-cooled reactors, pressurized water reactors, and liquid-metal fast breeder reactors (LMFBRs). The comparison is done in the form of q = Q/A (kW/m2), where Q is the reactor thermal output (in kilowatts) and A is the total heat transfer area (in square metres) of the SG. It is found that the HTGR SG has unexpectedly excellent characteristics, in spite of the low expectations of the gas-heating SG. In the area of heat transport capability, the HTGR SG is by no means inferior to (and may be superior to) light water reactors and LMFBRs. The reasons for this are explained and analyzed. The q value directly affects the design of the SG and the reactor, thus having a great impact on the cost of the plant. The greater q value of the HTGR SG lends optimistic views on the economics, at least on the HTGR SG design.