As you spend time battling and exploring the Wild Area in Pokémon Sword and Shield, you are going to start collecting a type of currency called Watts.
This is a brand new sub-currency not found in any other Pokémon game and is collected through interacting with markers known as dens across the different biomes. Once you collect enough Watts you can exchange them for special Pokéballs, Technical Records, and other useful items, some of which are found exclusively in the Wild Area.
It isn’t hard to collect them either since all you have to do is find any glowing den and press the A Button to begin an interaction. The amount of Watts you can earn from each den differs depending on how active it is, but even collecting a small amount adds up with how many raid spots there are.
Each den is used as a hub for potential raid battles in the Wild Area, with the biomes changing weather conditions and hosting different Pokémon with every switch. Depending on which area and what the weather is, different Pokémon will appear as raid bosses.
However, that doesn’t affect the Watts you can gain from interacting with them.
A dimly lit den, which is one that does not have an active raid available within it gives you 50 Watts when you click on it. And if you approach one of the pillars of light that signify a den has a raid ready to participate in, you get 300 Watts without even having to compete in the event.
This is a good way to stock on special Pokéballs like Dusk or Quick Balls because they only cost a fraction of their normal price and are valuable tools for completing your Pokédex. Some of the TRs are also great, but those are pretty pricey, so pick which ones you want ahead of time so you can save up.
You can also use Watts to upgrade your Rotom Bike with a faster charge time for that always helpful speed boost. The first upgrade costs 1,000 Watts, the second one 3,000, and so on until you max it out.
If you plan on spending a lot of time in the Wild Area early on, you should always stop to collect Watts, even if it is only the 50 from a dim den. Even a little will eventually help you pay for something in the end, which could make your adventure just a little less tedious.