Randall Munroe answers some absurd questions; Danielle George reveals what’s in store for this year’s Royal Institution Christmas Lectures; Jim Al-Khalili explores the strange world of quantum biology
Save: £49 per month
Fresh fruit, veg and meat (and cooking everything from scratch) may seem like the best way to eat economically, but the truth is that supermarket junk foods are hard to beat on price. A box of 10 budget fish fingers costs 56p and a tin of value baked beans (28p) will provide fibre and amino acids, while a glass of long-life orange juice (15p) will provide 80 per cent of your daily vitamin C requirements. The result is a meal for under a pound. This diet is a little too high in salt and lacks some micronutrients, but it would take a long time before your health suffered. Assuming a daily food budget of £10, spending a quid on your three meals a day for one week to plug the gap until payday will save £588 a year. So it’s a viable option, whatever Jamie Oliver might say.
Save: £42 per month
For the other 40 weeks, you can cut out brands to save 20 per cent on a £70 weekly shop. Supermarkets often price items in tiers: a premium range; brand-name products; supermarket own-brand; and finally the economy range. According to Martin Lewis of moneysavingexpert.com, much of the perceived difference comes from the brand identity and packaging, not the food itself. If you decant foods into neutral containers or just hide the label from your family, you can drop two quality tiers (and £560 a year) without anyone noticing.
Save: £90 per year
Adding fresh herbs makes cheap food seem more exotic. Basil, coriander and parsley are easy to grow in pots on your windowsill, mint grows like a weed, and a rosemary bush will last almost forever once established. A packet of 800 basil seeds costs 99p – the same as a single packet of cut leaves (air freight increases costs), so buying two packs a week is £100 a year. Growing your own costs under a tenner.
Save: £70 twice a year
Most households have enough food in cupboards and the freezer to last between one and four weeks.So twice a year, try not shopping at all. We tend to shop weekly for perishable items such as milk and fruit; once we’re in the store, the science of marketing compels us to spend more than we need.
Save: £74 per year
Tumble dryers need huge amounts of electricity to run because they remove water by evaporating it. The hydrogen bonds between water molecules are very strong and require a lot of energy to break. A tumble dryer uses 2.4kW, most of which is powering the heating element.
Spin dryers drive the water out centrifugally: not evaporating it makes them much more efficient. Most washing machines spin clothes, but the maximum speed is typically 1200rpm – a spin dryer does 2800rpm. Clothes won’t be fully dry when they come out, but you’ll almost halve drying times. A two-hour cycle in a 2.4kW tumble dryer costs 72p (15p per kW hour), a 400W spin dryer running for three minutes costs 0.3p. Assuming four loads per week, you’ll save £74.26. A new spin dryer costs about £85 so it almost pays for itself over one year.
Save: £3.30 per week
A typical flight of stairs is 2.6m high, and it takes 750 Newtons of force to lift a 75kg adult to the top, which gives almost 2000 joules of extra potential energy. But your muscles are only 20 per cent efficient, so they’d actually expend 10,000 joules. There’s no net change in your potential energy if you run straight down again, so the whole 10kJ is turned to heat. If it takes five seconds to run up and down, you’ll be generating heat at a rate of 2kW per hour, the same as a two-bar electric fire.
Doing this a few times an hour will keep you warm and save cash: an electric fire costs 15p per unit (30p an hour), so by heating yourself using the stairs for an hour a day on weekdays plus three hours on Saturday and Sunday, you’ll save £3.30 a week, or £171.60 a year. And you’ll be keeping fit.
Save: £5 a night
You don’t need alcohol to get drunk. A study of 150 students in New Zealand showed all the signs of intoxication when they believed they were drinking vodka, tonic and lime, even though the drinks contained no vodka. So save money when it’s your round by skipping or reducing the alcohol in some drinks. For example, buy a single vodka and Red Bull instead of a double. Do that for the last round on a Friday night and you’ll save a fiver. (If you get found out, you’ll save even more when the invites to the pub dry up.)
Save: £20 per month
Generally, when you start on the tequila or sambucca, the evening’s already getting out of hand. Shots are an expensive way to drink: they’re over very quickly and you’ll soon be queuing up for another, while the high alcohol concentration (typically 40 per cent) causes your stomach lining to become irritated and produce more mucus. This delays absorption so you won’t initially feel much effect and you’ll keep drinking for longer, which costs more and worsens the hangover.
Drinks with 10 and 30 per cent alcohol that contain a fizzy mixer move quickly from the stomach to the small intestine, where the alcohol is efficiently absorbed, letting you pace yourself better. So if a ‘swift one’ on payday turns into an all-night bender, save yourself the £20 on two rounds of shots and get some classy mixers instead. Your wallet – and liver – will thank you in the morning.
Save: £40 a night
A survey by SpeedDate.com showed that the most popular date activity was a romantic candlelit dinner for two at home. No fish fingers this time, though! A restaurant will easily set you back £60, while a meal and bottle of supermarket plonk is achievable on £20. Treating your significant other every week is £2080 saved a year.
According to a 30-year study of marriage types, one category most at risk of divorce also has the highest reported sexual satisfaction. The so-called ‘operatic marriage’ occurs when partners are emotionally volatile, with big swings between the highs and the lows. Blazing rows often lead to great make-up sex, but that level of instability eventually ends in divorce. The average cost is £7000 to each party during the first year following a divorce. That’s just legal bills, childcare and other extras, and doesn’t factor in the cost of selling the house or getting the paint off your suits.
Save: £10 per week
Cats, rabbits and guinea pigs are all generally free to a good home, and cost about £500 a year to look after. Dogs can cost double this when you factor in vet bills and insurance, but a dog will also provide you with exercise, so you can set this against the cost of gym membership or trips to the swimming pool.
Humans first started associating with animals about 15,000 years ago and there’s evidence to suggest that we’ve evolved to enjoy animal companionship because of the survival benefits it confers. Stroking an animal releases oxytocin into our bloodstream, a hormone that makes us feel calmer, more sociable and more loving to our family. By itself, this won’t save you money, but research shows that the less anxious you are, the less likely you are to indulge in compulsive shopping or drinking. If a pet makes you calm enough to need fewer stiff drinks or one less DVD bought on a whim, you’ll save £10 a week and you’ll soon break even on pet care costs. After that, everything’s profit.
Save: £25 per month
TV feels like a free form of entertainment as the set is already sitting there. And if you’re going to watch anything at all, you need to pay the licence fee, so surely the more you watch, the better value you get?
Actually, the more hours you watch, the more money you’ll spend: larger TVs, Sky and cable subscriptions, plus pay-per-view packages are all associated with high television use. And a 2008 study at the University of Maryland found that watching television is the only activity happy people consistently do less than unhappy people. Make do with Freeview and iPlayer and you’ll save around £25.
Save: £327 per year
If you play computer or videogames, you might spend £40 a month on a game that takes 20 hours to complete – that’s £2/hour. A massively multiplayer online game like World of Warcraft costs about £45 to buy, then £9 a month to play, but you’ll never complete the game and new worlds and adventures are added continuously. So if you play for a few hours, five nights a week, you’re paying under 30p/hour for your first year’s play.
Save: £8660 over six years
The hybrid technology in the Toyota Prius has made it the poster boy of fuel-efficient motoring since it first went on sale globally 10 years ago. The figure of 50 miles per gallon, as measured by the US Environmental Protection Agency, certainly looks impressive next to the 32mpg of a Ford Fiesta. But given that the on-the-road cost for a basic Prius is £11,300 more than the equivalent Fiesta, and assuming you replace your car every six years, that’s a £1883 per year premium.
So do fuel savings make the Prius cost effective in the long term? In the UK, the average number of miles driven annually is 8000 and, at £1.30 per litre of petrol, that translates to a difference of 5.5p per mile, or £440 a year. Taking this off the price premium gives a £1443 saving. Even if servicing, maintenance and other running costs were the same, you’d need to drive over 200,000 miles to recoup your initial investment – that’s 25 years.
Save: £37 per month
The power required to overcome wind resistance rises with the cube of your speed. So it requires over 12 times the power to push the air out of the way at 70mph than at 30mph. Ditching the roof rack reduces drag by up to 10 per cent, while turning off the air-con can also save 10 per cent, but only if you can stay cool with just the air vents. If you open the windows, the extra drag at speeds above 55mph will outweigh the saving.
Correctly inflating your tyres will reduce rolling friction because the contact area between the tyres and the ground is smaller. According to the US Department of Energy, every 1psi of under-inflation costs 3.3 per cent in fuel efficiency. So if your tyres are 3psi under-inflated, pumping them up means another 10 per cent off fuel costs. Based on fuel economy figures and assuming 8000 miles a year in a 32mpg car, you’ll spend £1477 a year on fuel. So in total, a 30 per cent reduction in drag and friction would save £443 per year.
Save: £3 per week
Unless your car is a hybrid with regenerative braking, the brakes work by converting kinetic energy to heat, which is vented to the atmosphere and lost. Braking is a waste of fuel because you need to burn extra to build speed back up again. According to the RAC, this costs £3 a week.
Anticipate stops early and reduce your speed by coasting. Time it right and lights will turn green as you reach them and, as you’re still moving, you won’t have to accelerate from zero. Even if you don’t, coasting is more efficient than braking because most fuel-injected petrol engines cut the fuel to the engine when you let go of the accelerator, provided the revs stay above 1500. So as you slow down, you don’t use any fuel at all. Although, driving safely and avoiding accidents takes priority over saving a few quid.
Save: £100 (300,000 pesos)
A cognitive bias known as the ‘money illusion’ means we tend to think of currency in terms of its nominal value, rather than its purchasing power. So $100 dollars feels like more than £62, even though they’re about the same. You could use this effect to your advantage in Colombia, where there are over 3000 pesos to the pound. A meal at a cheap restaurant will cost tens of thousands of pesos, so you’ll tend to be more careful with your money. The numerical value of the currency might make you aware enough of your spending to save £100 on expendable extras. Another cognitive bias, called the ‘denomination effect’ means you’re less likely to spend larger bills than the equivalent amount in smaller bills. So keep your money in 50,000 peso notes where possible.
A fortnight in Ibagué, Colombia, volunteering in a botanical conservation project (www.anyworkanywhere.com) will cost you £1147 including flights for the middle of July. By helping scientists with their research you’ll save £1845 compared with a comparable package holiday to Cartagena.
The British are terrible at haggling, and we make things harder for ourselves by sticking to English. Cognitive research shows we give preferential treatment to members of our own groups, even if those groups are fairly spurious. So learn enough Spanish to conduct a negotiation and mention, in passing, that you’re visiting because you have relatives there, and you’ll create an unconscious, favourable bias among the locals that should help you bag a bargain. Brits abroad spend about £300; knowing the language will save you 5-10 per cent each time.