22 August, 2015

Fuel economy in a car: Charging the battery the Arduino way - Part One

In this post we will see what details we consider to adapt a vehicle to save fuel by switching off the alternator when we are not interested to charge the battery (and take advantage of braking, engine braking, etc. to do so), taking advantage of lessons learned in the previous post . This It is especially useful in a diesel , where power consumption is much lower than in a gasoline car.

Currently any measure is little to lower the consumption of a car, and although we are in a period of decline in fuel prices, this is transitory, because as with any commodity product high demand prices will soon go back up (or keep at the highest possible price that permits its competitors).
We can change the wheels to a eco profile ones, change the oil by other more energy efficient (as we discussed), etc. And one of the points of great savings capacity (between 1 and 5% savings) is in producing electricity, generating electricity with oil is very expensive. Some people even partially hybridized vehicle for changing the alternator motor / generator and replacing the battery with a LifePo4 (Forum GoldenMotor).
You have to evaluate the suitability of this modification, as the lead-calcium batteries do not allow more than 20% discharge without damage, so there is little room to use them with a programmed charging. Ideally mount a LiFePo4 battery, but can cost more than 200 €, only useful and profitable to people that uses them a lot in short travels in the city (taxi drivers and transport vehicles).
The most innovative engines are now including programmed battery charging, so that is only activated when the low voltage level is reached, although I do not know what kind of battery this cars uses and what the procedure in detail.

Curiously, in the following video you can see how the workload on the alternator note clearly appreciate the drop in rpm (and automatic adjustment by the control unit) of this PSA 1.6 HDI diesel engine: