Electric Water Pump for Car, BMW Electric Water Pump Supplier in China

Electric water pump is installed into HEV, EV or FCV in order to cool down the surrounding devices of these vehicles.　Conventional mechanical water pump is powered by combustion engine to circulate coolant around the engine. Volume of coolant is in proportion to the engine revolution. Just control of coolant volume on demand is not mechanically possible. It may either overcool or undercool.

Electric water pump is activated by battery and motor only on demand for cooling. The just function minimizes the load on engine.

To understand why anyone would want an electric water pump, first you need to understand the purpose and drawbacks of a traditional, mechanical water pump. Technically, it's a coolant and anti-freeze pump, but we'll call it a water pump for short because that's how most auto technicians refer to it.

The traditional water pump is a belt-driven (or sometimes cam-driven) component. In other words, it takes mechanical, rotational energy from the engine -- provided in the form of a spinning rubber belt -- and uses it to drive an internal pump mechanism. An impeller in the pump sends engine coolant on a winding journey through the engine block to absorb heat, then on to the radiator, where the coolant sheds heat and then back through the pump again.

With its water pump running, a typical auto engine remains in the relatively comfortable neighborhood of about 200 degrees Fahrenheit (93.3 degrees Celsius) and everybody's happy, including your car. So why mess with such a good thing by throwing an electric-powered version into the mix?

Here's the thing: Any accessory that runs off of the energy of an engine belt is costing you. It either robs the vehicle of horsepower, fuel economy or both. You know how sluggish your vehicle gets and how your fuel mileage goes down when you drive with the air conditioning on? That's because the engine needs to work harder to power the belt-driven AC compressor and still maintain a constant speed. That same parasitic energy loss is going on all the time as far as your water pump is concerned.

An electric water pump doesn't need belt power. Instead, it runs on battery power. So, you might be wondering, since that pesky law of thermodynamics states that you can't create or destroy energy, aren't you just putting a bigger load on the (belt-driven) alternator, which provides energy to recharge the battery? Won't the energy losses have to be made up somewhere else and affect performance?

In a few words, not in a way that you'd notice. The law of thermodynamics does still hold true. However, mechanical water pumps spin all the time, at a speed proportional to engine speed. As a result, sometimes you're pumping lots of coolant when the engine isn't hot enough to actually need it. That's wasted energy. Sometimes your engine needs more cooling than it gets, like right when you shut your car off after hard driving on a hot day. That can wear out some engine components faster.

An electric water pump, conversely, allows the manufacturer to set (with much more precision) how much coolant courses through the engine at given temperature ranges. So it's actually more efficient and more in tune with your engine's specific cooling needs.