I would like to suggest two changes to the rendering of Wind Turbines,
at least in the default tile rendering (mapnik).
Not sure I like the change some months ago to the look of the icon; I think it looks too much like an old-fashioned fan and the previous icon design looked more like an actual wind turbine.
I would really like to see them rendered at zoom levels higher than the current lowest zoom levels so that I don’t have to zoom in so far to see where existing wind farms/ranches are. I am also wondering if information on parcels of land where wind farms reside should perhaps be used to create a polygon boundary for the extent of any given wind farm? Presently the wind turbines don’t show up until you have zoomed in to level 15; I think they should start to be rendered at zoom level 13. Many wind farms are works in progress, being built in phases, adding more turbines amidst existing turbines and/or expanding the geographic extent outward, and I like to keep up with them as much as possible…so it’s nice to be able to find them easily by panning around. When looking for a wind farm to see if it has been mapped at all or if it needs work, most sources only give the name of a nearby town, which results in needing to “look around” large agricultural areas.
I actually like the new icon, its compact and doesn’t clutter up the map. The previous version one was way to big, taking up to much space.
In terms of true “wind farms”, with dozens or hundreds of turbines owned by a single entity, versus dispersed single-owner turbines that you often see near agricultural farms, you may consider adding a "power=plant, plant:source=wind tag to the outline or convex hull around all turbines, and adding the power=generator, generator:source=wind to the individual wind turbines. This will “group” the individual turbines into what they essentially are: a single power plant with multiple generators, and potentially make them more visible on the map.
I would only do this if the “wind farm” is not heavily interspersed with other stuff, like buildings of farm houses as such, as otherwise it would become unclear if these building and other features actually belonged to the power plant (which in most cases of a wind farm they obviously wouldn’t).
As to the zoom, you may consider posting a request for a change at:
which is the Github repository of the main style.
Personally, I don’t think it would be wise to change the zoomlevel to Z13. At that scale, some windfarms with smaller densely spaced turbines, will become a single blob of overlapping turbines. Maybe Z14 is just feasible, but it would be up to the style maintainers to judge this.
E.g. see this small “wind farm”, and try imagine it at Z13 by zooming out:
I don’t think it would work… all 11 turbines would be squeezed into the space of 4 turbines at Z15 and start overlapping.