Transforming the Twentieth Century: Technical Innovations and Their Consequences

In contrast, electricity intensity continued to increase even after 1950: electricity

Cost advantages drove this innovation: minimills, dispensing with blast furnaces, needed much lower capital investment (only 15–20% of the total needed for new BFs), and their operating costs were also considerably lower as continuous casting eliminated the equipment and energy needed for reheating and shaping the ingots

There are only three major classes of fossil fuels (coals, crude oils, and natural gases) and five major renewable energy flows (direct solar, wind, water, tides, biomass), and only a handful of prime movers (steam, water, wind, and gas turbines and internal combustion engines) are used to convert these energies into electricity, heat, and motion.

the most advanced GT of the late 1990s, GE’s MS9001H, rated 480 MW in 50 Hz combined cycle mode (i.e., with the recovery of exhaust heat) and had an inlet temperature of 1427°C, and its rate of 6 MJ/kWh resulted in the unprecedented efficiency of 60%

Finally, CO2 (in steam reforming of natural gas: 7.05 kg of this gas is produced per kilogram of hydrogen)

Comparisons for the Western world show that during the 20th century life expectancies rose from the mid-40s to the late 70s; cost of food as the share of disposable income fell by anywhere between 60% and 80%; virtually all households had electricity supply and were saturated with telephones, radios, TVs, refrigerators, clothes washers, and microwa

Steam produced by the exhaust heat can be also used for industrial processing or to heat buildings in cogeneration (combined heat and electricity) plants.

This high efficiency also translates into a much reduced specific generation of CO2: steam turbine generation fueled by coal produces more than 1 kg CO2/kg, and by fuel oil, at least 0.8 kg, while CCGT will emit less than 0.4 kg/kWh (Islas 1999). Other environmental advantages include the fact that GTs do not require any external cooling and that n

an incomplete and imperfect story of amazing technical transformations that is told from a variety of perspectives in order to understand better the complexities of the fascinating process, its stunning accomplishments, and its unforeseen (and often unforeseeable) failures.

BFs are prodigious (Peacey and Davenport 1979; Sugawara et al. 1986). A furnace producing 10,000 t of metal a day will need more than 4.5 Mt of hot blast air a year, and it has to be supplied with about 1.6 t of pelletized ore, 400 kg of coke, 100 kg of injected coal (or 60 kg of fuel oil), and 200 kg of limestone for every tonne of iron. These cha