90Paper has an embodied energy of 10 kWh per kg. Making newspaper from virgin wood has an energy cost of about
5 kWh/kg, and the paper itself has an energy content similar to that of wood, about 5 kWh/kg. (Source: Ucuncu
(1993); Erdincler and Vesilind (1993); see p284.) Energy costs vary between mills and between countries. 5 kWh/kg is
the figure for a Swedish newspaper mill in 1973 from Norrström (1980), who estimated that efficiency measures could
reduce the cost to about 3.2 kWh/kg. A more recent full life-cycle analysis (Denison, 1997) estimates the net energy
cost of production of newsprint in the USA from virgin wood followed by a typical mix of landfilling and incineration
to be 12 kWh/kg; the energy cost of producing newsprint from recycled material and recycling it is 6 kWh/kg.
91The energy intensity of road transport in the UK is about 1 kWh per t-km. Source: www.dft.gov.uk/pgr/statistics/
–The energy intensity of freight transport by this container ship is 0.015 kWh per ton-km. The Ever Uberty – length 285 m,
breadth 40 m – has a capacity of 4948 TEUs, deadweight 63 000 t, and a service speed of 25 knots; its engine’s normal
delivered power is 44 MW. One TEU is the size of a small 20-foot container – about 40 m3. Most containers you see
today are 40-foot containers with a size of 2 TEU. A 40-foot container weighs 4 tons and can carry 26 tons of stuff.
Assuming its engine is 50%-efficient, this ship’s energy consumption works out to 0.015 kWh of chemical energy per
–Britain’s share of international shipping... Source: Anderson et al. (2006).
92Figure 15.8. Energy consumptions of ships. The five points in the figure are a container ship (46 km/h), a dry cargo
vessel (24 km/h), an oil tanker (29 km/h), an inland marine ship (24 km/h), and the NS Savannah (39 km/h).
Dry cargo vessel 0.08 kWh/t-km. A vessel with a grain capacity of 5200 m3 carries 3360 deadweight tons. (Dead-
weight tonnage is the mass of cargo that the ship can carry.) It travels at speed 13 kn (24 km/h); its one
engine with 2 MW delivered power consumes 186 g of fuel-oil per kWh of delivered energy (42% efficiency).
Oil tanker A modern oil tanker uses 0.017 kWh/t-km [
engine: 11.2 MW maximum delivered power. Speed at 8.2 MW: 15.5 kn (29 km/h). The energy contained in the
oil cargo is 520 million kWh. So 1% of the energy in the oil is used in transporting the oil one-quarter of the way
round the earth (10 000 km).
Roll-on, roll-off carriers The ships of Wilh. Wilhelmsen shipping company deliver freight-transport with an energy
cost between 0.028 and 0.05 kWh/t-km [ ].
92Water delivery and sewage treatment costs 0.4 kWh/d per person. The total energy use of the water industry in 2005–6
was 7703 GWh. Supplying 1 m3 of water has an energy cost of 0.59 kWh. Treating 1 m3 of sewage has an energy cost
of 0.63 kWh. For anyone interested in greenhouse-gas emissions, water supply has a footprint of 289 g CO2 per m3 of
water delivered, and wastewater treatment, 406 g CO2 per m3 of wastewater.
Domestic water consumption is 151 litres per day per person. Total water consumption is 221 l/d per person. Leakage
amounts to 57 litres per day per person. Sources: Parliamentary Office of Science and Technology [www.parliament.
uk/documents/upload/postpn282.pdf], Water UK (2006).
93Supermarkets in the UK consume 11 TWh/y. [ ]
–Helm et al. suggest that, allowing for imports and exports, Britain’s carbon footprint is nearly doubled to about 21 tons.
Helm et al. (2007).