Patio stoves: are they useful?

What would humanity be without its tireless desire to achieve the impossible? Among other things, we couldn’t fly planes or cure serious illnesses, but surely the planet would be cleaner, with more rhinos and orangutans, and we wouldn’t have global warming.

In some utopias, like finding the Philosopher’s Stone or the submerged city of Atlantis, we’ve already given up, but in others, like heating an outdoor space in the dead of winter, we keep trying.

“It’s impossible”, begins by explaining María Luisa del Campo, director and academic of the technological center yarmulke , from the University of Talca, where he specializes in energy efficiency. “In an open space, such as a patio, deck or balcony, as quickly as heat is generated, it is lost. Nearly 80% of the energy is transmitted to the environment, so it is not recommended to heat an outdoor space.

Miguel Castro, professor of construction engineering at Duoc UC de Alameda, agrees with her. “Since there is a constant flow of air in an open space, almost all the heat produced goes away,” he says. “So having an outdoor stove is neither durable nor cheap.”

But as long as the spirit of Nicolás Massú lives on…”nothing is impossible, eh…, no eh… ”-, there will be no shortage of those who continue to try, again and again, to heat the unheatable. For them, with these two experts, we will see which are the least inefficient and most reasonable alternatives among terrace stoves.

In this context, of which ninguna option is completely recommendable, the que para Miguel Castro siendo la más efectiva es la estufa de patio a gas, para cilindros de 11 y 15 kg, que tiene formed de hongo, con un specie de sombrero metallico en the upper portion.

“Although their power and efficiency depend on the model and brand, these stoves or heaters generally use 800g of gas per hour or more, they have a heating radius of 3 meters and, thanks to this hat, the heat is radiated more horizontally,” says Professor Duoc UC.

“We must not forget”, specifies the academician Del Campo, “that the heat rises, so this plate that they have on the top – called deflector, according to the manufacturers – is the one that manages to keep it at our level” .

The problem, she says, is that the only way to take advantage of that higher temperature in an open space, like a patio or deck, is to be very close to the stove. If you take a step or two, it’s like the heater isn’t there.

There are also pyramid-shaped models, “more efficient”, according to Miguel Castro, but also much more expensive: they can be worth more than double the previous one. “Its advantage is that it has a tube that radiates heat throughout its elevation, which gives it more power.”

Castro also mentions biomass heaters, which use pellets as fuel. “The initial cost of the device is higher – its price is usually between 350 and 500,000 pesos – but the consumption is lower: they have an approximate output of 1.8 kg per hour.”

In this article on indoor stoves, we have already mentioned how electrical appliances are inadvisable. They spend a lot of energy and generate little heat. We’re sorry to say that they won’t do much to heat your balcony or terrace either.

“They have a very low radiation capacity and a very high consumption”, explains María Luisa del Campo. “Zero effective”. Miguel Castro thinks the same thing: “we have not yet reached the moment when electrical appliances manage to generate enough heat with an appropriate energy expenditure. For the moment, these stoves heat less and consume the same or more than other fuels”.

That is to say: if an electric stove is not ideal for heating the interior of your house or your apartment, it will be less so for the exterior.

But in the description of an electric patio heater it is stated that its power is 1500 W, similar to that of a gas heater. Shouldn’t it get hot? No, Castro said. “Don’t be confused: Wattage, which is measured in watts (W), is the amount of energy an appliance produces or consumes, different from heat capacity, which is usually measured in BTUs (British thermal unit)”.

That is, the fact that they have the same power only guarantees the amount of energy they will consume, not the heat they will generate.

If, despite everything, you are still convinced to acquire a terrace stove, María Luisa del Campo, from the University of Talca, suggests intervening in the space so that it is not so open, thus allowing the heat to stay a bit in the place longer.

“A good strategy would be, as we do in bars or restaurants, to close with plastic curtains, for example, and create some insulation,” he says. “Only with this can great change be generated.”

“Instead of losing 80% of the heat”, adds Miguel Castro, “you will only waste” 50%. house.” This material helps a lot to maintain the temperature.”

Also take advantage of remembering that these stoves are designed for small spaces, not large patios or open plots. “Outside, none of these heaters are working.” There it would be more convenient to light a grill and uncork a bottle: it is much more likely that no one will get very cold that way.

*Prices for products in this item are updated as of June 9, 2022. Values ​​and availability may change.