Formula 1's Energy Recovery System (ERS) has been in the sport in its current guise since 2014 and has been a part of Grand Prix racing for the previous decade. The system is what turns the petrol Internal Combustion Engine (ICE) into a hybrid, as it adds around 160 bhp to the car's output. That's more power than most road cars have in total, so it makes a huge difference to the car's performance. Learning how to master the management of ERS is a steep learning curve, but we're going to guide you through the ins and outs of the electric motors.
In F1 2019, the ERS has six modes of deployment, which include; none , low , medium , high , overtake  and hotlap . The best way to understand what these modes mean is to imagine them as the fuel modes, but the key difference is that instead of it being constantly drained, it's recharged during the braking zones.
Most of the energy that's recovered is done so kinetically, with the brakes heat transformed into battery power to propel the car forward. This means that the rate at which it recharges varies with each circuit. For example, the street circuits of Singapore and Monaco have more braking zones and less long straights than most circuits, so you can use higher discharge rates more frequently.
In general, though, the Medium setting keeps you at around neutral in terms of using and recharging.
If you're wondering about classic cars and Formula 2, it's only the 2019 cars that have KERS in, as the system wasn't used in 2010 and isn't used in F2.
Like anything in racing, there are the right ways to go about being fast and the wrong ways. Aside from at the start of the race, where you should be in hotlap mode to gain as many places as possible, you'll usually be in the bottom three ERS modes.
Like with the fuel, use the higher ERS modes on the straights and areas where the AI are more likely to pass you. This gives both the benefit of being faster when you're by yourself and defending from faster drivers behind.
Obviously, in qualifying, use hotlap mode as much as possible, but not all the time. You'd think having the highest ERS mode at all points of the track would be fastest, but you'd be wrong. Hotlap mode gives you the most power in all gears except for eighth, where overtake mode is faster. Overtake mode should be switched to when the car is in top gear, even in qualifying.
Just be aware, that you won't always have enough deployment to last a whole lap, and being left with no battery in the final sector can ruin a qualifying lap so it will be vital to find the spots where you can drop your deployment mode down and save some life. For example, the middle sector of Monza and Spa are the perfect spots to drop into medium to save the power for the long straights.
ERS help is available
I know what you're thinking, for some players, it's hard to manage the fuel alone, without considering the ERS. If that's the case, you can disable the ERS simulation in the assists menu. However, if you're looking for that extra challenge, the ERS is manageable with practice.
In general, I use none or low in the areas where you can't overtake, medium in the areas where it's possible and high on the longest straight or two. If you have some extra from Safety Cars or VSC's, use overtake mode to get past another car on the straight or to lower your lap time when around a pit-stop.
What you absolutely have to avoid, though, is running out of deployable energy, as being with none will leave you vulnerable to attack.
Practice is crucial
Like a with the tyre wear and fuel usage, there is a practice programme in Career Mode that will show you how to save electric energy around the track you're racing on. You'll get resource points as a reward, so it's worth completing. However, I find it to save too much energy and you'll be using the system more aggressive during a race situation. Alternatively, you can practice online or set up a race in Grand Prix mode.