In the smartphone charging wars, Oppo uses its own VOOC charging technology rather for USB fast charging charging rather than the more standardized USB Power Delivery.
Oppo has been very aggressive, releasing 20W VOOC 3.0, 30W VOOC 4.0, and 65W SuperVOOC 2.0. To take a closer look at how much power is actually delivered by these VOOC technology variations, we use the GRL-C2 USB PD Tester and GRL-PSP Power Analyzer software from Granite River Labs.
One of the noticeable differences in how Oppo claims power ratings on its chargers is that 20W, 30W, 65W refers to how much power the VOOC chargers consume from the AC outlet. USB Power Delivery power ratings refer to how much power is coming out of the charger's USB-C port.
The VOOC 3.0 charger consumes a max 20W from the AC outlet but delivers ~16W over USB, which is about an 80% power efficiency level.
Similarly, we see that the VOOC 4.0 charger consumes a max of 27W and delivers 21W, which is equivalent to 77% power efficiency.
SuperVOOC 2.0 consumes a max 68W and provides 57W of USB power, or 84% power efficiency.
Another important observation is that the max power provided by the VOOC 4.0 and SuperVOOC 2.0 chargers only get provided by a very short period of time. Most of the charging takes place at much lower power charging levels compared to VOOC 3.0, ironically resulting in slower charging using these newer VOOC technology versions.