also refrigerates food on its way from field to shopping basket. I’ll estimate

the power cost of the food-chain later, in Chapter 15.

Our rough estimate of the total energy that one person might spend on

heating and cooling, including home, workplace, and cooking, is 37 kWh/d

per person (12 for hot water, 24 for hot air, and 1 for cooling).

Evidence that this estimate is in the right ballpark, or perhaps a little

on the low side, comes from my own domestic gas consumption, which

for 12 years averaged 40 kWh per day (figure 7.10). At the time I thought I

was a fairly frugal user of heating, but I wasn’t being attentive to my actual

power consumption. Chapter 21 will reveal how much power I saved once

I started paying attention.

Since heating is a big item in our consumption stack, let’s check my

estimates against some national statistics. Nationally, the average *domestic*

consumption for space heating, water, and cooking in the year 2000 was

21 kWh per day per person, and consumption in the *service sector* for heat-

ing, cooling, catering, and hot water was 8.5 kWh/d/p. For an estimate

of workplace heating, let’s take the gas consumption of the University of

Cambridge in 2006–7: 16 kWh/d per employee.

Totting up these three numbers, a second guess for the national spend

on heating is 21 + 8.5 + 16 ≈ 45 kWh/d per person, if Cambridge University

is a normal workplace. Good, that’s reassuringly close to our first

guess of 37 kWh/d.

page no.

50*An oven uses 3 kW*. Obviously there’s a range of powers. Many ovens have

a maximum power of 1.8 kW or 2.2 kW. Top-of-the-line ovens use as much

as 6 kW. For example, the Whirlpool AGB 487/WP 4 Hotplate Electric Oven

Range has a 5.9 kW oven, and four 2.3 kW hotplates.

www.kcmltd.com/electric oven ranges.shtml

www.1stforkitchens.co.uk/kitchenovens.html