Air Conditioning vs. Windows Down: Which is More Efficient?


Sometimes when it’s warm outside, all people want to do is get cool as fast as possible. Believe it or not, driving with your air conditioner on can be more efficient than driving with your windows down, depending on the situation, and vice versa. We’ve decided to shed some light on the classic air conditioning vs. windows down debate.

According to Discovery, context is everything. Determining which method is better means looking at efficiency and drag. Using the air conditioner will lower your car’s efficiency because it takes power away from the engine. Though it varies from model to model, having the A/C on generally reduces efficiency by a whopping 10%.

When considering your windows, drag is everything. Most vehicles are incredibly aerodynamic – with the windows up. That means at high speeds, having your windows down could increase drag substantially. When on the highway, having all your windows down could increase drag, ergo reducing efficiency by more than 15%.

So which is better? When driving at low speeds, roll your windows down. In town, you probably won’t notice much of a difference. On the highway, sticking to the A/C may actually save you money in the long run.