Getting beyond 17th century technology is not that hard. It only took us... a long time.
Anyway, you can have effective 17th century technology without the need of excessive wood (lets say a fixed quantity of wood or similarly rigid material (I like the Fibreglass idea mentioned by @Madlozoz), not greater than that that is required to build your ship, and not consumed in the process of use. (so you're not relying on "wood * x = power")
You have a couple of really good options when you're at sea. You can have a tidal piston, Create a Moon-pool in the center of the ship, with walls that terminate above the waterline (preferably with a bit of margin to spare). When your ship moves through the water, the water in the moon pool acts as an air pump. You can harvest the effect to generate a reasonable amount of energy while in transit (and even when stationary in turbid waters). (I'll come back to 'energy in a moment').
Another option is the use of the traditional Windmill (woohoo for windmills). I would be tempted to say 'replace the mainsail with a windmill' but that would ruin the aesthetics. Regardless, a windmill will work when anchored, and when you're not anchored, it will still work, just not as effectively.
Coming back to "energy", we should not mistake "energy" for "electricity". Energy is simply the available force that we can exert on something. Your bigger problem is the ability to store and release energy. Compressing gas is a pretty big ask for pre 17th century technology. And in your works Metal springs are probably a bit of a stretch... You might be able to use a Gravity Battery, hang a couple of heavy weights over the edge of your ship (Has the added advantage of increasing your ships stability (Drogue stones)).
If you don't mind a little of that electric tingle, you could split water into hydrogen and oxygen. (That would explain the elves squeaky voices, those hydrogen addicts (and long lives being in a rich oxygen environment)). Burning the hydrogen would give you a real kick, it's Hydrocarbon's without the carbons.
Once you have your method of Storing the energy, now you need a method for utilizing it. Lets go with the Gravity battery, because Elves don't like electricity. If you run a simple axel down the length of the ship, stem to stern. You could attach your gravity battery to it using ropes (very primitive but exactly exactly the same as how an early ships rudder was roped up to the tiller, many loops around the axle from the gravity battery and you have converted your Potential Energy into Rotational Energy (The most useful pre silicon age form of energy (IMHO)). Pretty simple clutch mechanisms can be used to couple/decouple machines from the energy supply.
Now you have;
- Two methods of generating energy without consuming any resources.
- Two methods of storing energy.
- A method of converting stored energy into useable energy.
Now all you need to run are the numbers, how much energy you can get from wind (quite a bit).
How much energy you can store (quite a bit).
How much energy you can use (Rope's can snap, and beams and splinter if you use too much energy).
And you can figure out from that, what you can do with said energy. You should have enough to perform most manufacturing tasks. The only 'hard' thing to do will be creating heat, You can probably do a lot with solar cooker technology though.
Now I know the tangent I went on is a little focused on 'create, store and use energy' but that's because technological advancement is very closely coupled to the amount of energy that a person is able to harness and use.