|electricity:origin=renewable, solar, wind, etc.
|Define the origin of the available electricity as renewable or from other sources.
Parent proposal: https://wiki.openstreetmap.org/wiki/Proposed_features/electricity
Add an electricity:origin tag that can be used as an additional information tag on amenities that provide electricity for public consumption. This could include car and bike charging stations, as well as camp sites.
This tag would allow interested consumers to filter for charging stations or camp sites that offer electricity through renewable sources. This electricity could stem from nearby photovoltaic systems, which would additionally be tagged seperately as a generator. It could also, however, be directly supporting renewable energy infrastructure through green pricing tariffs (in German: Ökostrom). In these schemes, electrical utility suppliers offer an optional surcharge to the electricity rate that allows both residential and commercial consumers to source up to 100 percent of their electricity from renewable resources. Often the electricity is sourced from a mix of renewable energies, potentially including solar, wind, hydroelectricity and geothermal power. These tariffs are very common in Germany and becoming increasingly popular in the United States.
Based on the values for generator:source, I would suggest the following tags
|Electricity comes from a mix of renewable sources, likely through a green pricing scheme.
|Electricity comes solely from photovoltaic generators, perhaps located nearby.
If there are no further specifics apart from "renewable" mentioned on the amenity, it shoud be tagged with electricity:origin=renewable. If multiple sources are explicitly named, then they should each be tagged in a semicolon-separated list, e.g. electricity:origin=solar;wind
When to tag
This tag should only be used if the origin of the electricity is mentioned on a sign or explcitly advertised in another manner. Checking the veracity of the supplied information is not the task of the mapper - they should instead base tagging on ground-truth. While some regions, such as the EU, guarantee that specific portions of electricity correspond to renewable energies, this is not yet the case worldwide.
Please see parent proposal: 
Please comment on the discussion page.