Heating oil: fill the tank now or wait?

Heating oil: fill the tank now or pay more in January

Fill the heating oil tank now or wait for prices to drop? It's the question that comes up every autumn in any home with an oil boiler, and this year there's an added twist: prices are moving fast and upwards. The short answer is uncomfortable. Waiting almost never pays off. For the 1,000 to 2,000 litres a detached house gets through, the difference between buying today and in a month isn't measured in coffees, it's measured in bills.

The calculation that shatters the «no rush» argument

With a small tank — a car's, 50 litres — a 20-cent difference is €10. A couple of coffees. That's the argument of those who say it's not worth rushing. The flaw is one of scale. A heating oil tank holds between 1,000 and 2,000 litres; with that range, every cent of increase weighs heavily. And the cents add up: some have seen the price per litre of heating oil go from €1.37 in Galicia (VAT included) to €1.44 in a matter of days. Seven cents that, on 1,500 litres, exceed €100.

Why the price has become nervous

International benchmarks don't help. Diesel in the United States topped $6 per gallon (3.78 litres) for the first time, according to GasBuddy data, and crude oil is trading under pressure from tensions in the Middle East and the Red Sea. Everything points the same way: when maritime transport gets complicated and inventories tighten, what someone filling their tank in a village in Burgos pays is the latest version of that chain. In Las Merindades, the litre drops to €1.35 if you buy 400 litres, but rises to €1.39 for just 200. Here, volume is money.

What a house really consumes: insulation rules

Consumption matters more than price. A 90-square-metre detached house, old and uninsulated, uses around 1,400 litres per winter, from mid-October to late March. Another of 80 square metres, in a mountain area at 800 metres altitude, with wooden windows and single glazing, expects to use a similar amount. Some budget over €1,800 just to heat the house until spring. And the regional contrast is brutal: in Valencia, four butane cylinders — about €65 — are enough to get through the entire winter.

Natural gas, firewood or solar panels: the alternatives

A range of options emerges against oil: natural gas, cheaper than heating oil; biomass and firewood, which many recover from the previous year; and solar panels, backed by night-rate storage for when there's no sun. Oil has one undisputed advantage: you pay for what you burn. With gas, the pessimists warn, there's always a standing charge, rate hikes and taxes even when the boiler is off.

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The recommendation from veterans of this market is clear and icy: fill the tank in early summer, when no one is thinking about heating and demand is minimal. Anyone reading this in autumn is already late. Which, given the outlook, is the most expensive news of the year.