Ever wondered why people talk about horsepower? Let us tell you what it’s all about.

How many horses is your car?

We must be honest; we’ve always been confused as to what it means when we hear the term – my car has 200 horsepower or 150 horsepower. Our presumption is that it is a ridiculous term and who cares how many horses are the equivalent to the power of your car?

It came to the forefront of my mind on the journey to school this week, when I was on the car phone to a dealership regarding a test drive of a new model. The salesman was giving the usual patter, “you’ll love the car, looks really nice, nippy too, 180  horse power.” After the call my inquisitive 9 year old, who unlike us adults, has no embarrassment over not knowing something chirps up with… “mummy is the new car powered by horses?”

“No,” I reply, “it’s just the way they describe how powerful the car is. The more horses, the more power.” I’m in uncharted territory here but I’m feeling quietly confident that was a good answer, until…

“Mummy, how big are the horses? Because big horses are more powerful than little horses.” – ooh good question and I’m stumped.

So why do we refer to how powerful a car is as ‘horsepower?’

Let me tell you…

It dates back to the introduction of steam engines. Before steam engines existed, everything was driven by horses. When James Watt invented the steam engine, he needed a way to simply describe the power of each engine in order to sell them. He referred to the power of each engine as “horse power” meaning how many horses would be equivalent to pulling a train carriage.

Although just to confuse things…

We can safely assume that 1horse power is the same output as the power of a single horse… NOPE! In fact a single horse can produce up to 15 horsepower! Confusing, I know! Interestingly a human can produce 1 horse power!?!? – clear as mud?

Despite the slightly muddled fact that 1 horse equals 15 horsepower, the term is used to describe the power output of the engine. The more horsepower, the more powerful the engine. (Store this fact for now!)

Engine size:

People often talk about engine size – the car has a 1 litre or 2 litre engine etc. But, how does engine size come into the equation I hear you ask. Generally, the bigger the engine the more powerful it is? Well no, I’m afraid not. The engine size although has an effect on the power output it can also dramatically change depending on how the engine is designed to perform. You may have noticed many cars, even large SUV’s, have smaller engines for economy but produce a decent amount of horsepower. For example the Nissan Quashqai has a 1.2 litre engine but produces 113 horsepower, that’s the equivalent of a VW Golf 1.6TDI. In a nutshell, you cannot determine the power of the car by the engine size.

What about electric cars?

Electric car’s power output is relatively easy, nothing to do with engine size, it’s simply measured in Kilowatts(KW). The more KW you have the more hold onto your hat power the car has. Some manufacturers do state the horsepower of electric cars as ‘some’ consumers find it easier, they calculate it from the KW so you can make a direct comparison (1hp = kW x 1.369) – simples!

What about Brake horsepower (BHP)? Well to put it in layman’s terms, it is measuring power just in a slightly different way.

Coco Chanel once said,

“I don’t care what you think about me. I don’t think about you at all.”

Remember this when you’re dealing with the salesman!

Basically, all you need to know is the higher the Horsepower (HP) or Brake Horsepower (BHP) or even Kilowatts (KW) the more powerful the engine is and chances are the faster the car will go! If you want to zip around go for a higher figure, anything above 180 HP or BHP is pretty powerful and you won’t go short on power or speed if that’s your thing! Just as importantly if you get any condescending questions about HP from a dealer (or other half) you now know the basics. Maybe ask them to explain where the term came from and does 1HP  = 1 horse??

Horse pic