As for the NB windmills, if their energy is sold cheap to Hydro Quebec so that it can reduce its hydro output to conserve water for future sale, it defeats the purpose of the non-polluting plants. Wind and solar plants should be constructed with the purpose to reduce the number of coal/gas/oil-fired plants.
But any time you generate power with windmills, and it's not needed immediately, you can offset some hydro and thus keep water behind dams (or pump water uphill). Or you can continue generating hydro and thus offset some thermal or nuclear generation. The dams can act as buffers to allow for the inflexible operating characteristics of thermal plants.
You can't offset hydro with other sources indefinitely because the dams eventually will end up full. (Or alternatively, empty.) In the late winter, many dams in BC have to spill water just to make sure there's capacity to accommodate the spring freshet without overtopping the dams or downstream flooding. Presumably as much of that spillage as possible is used to generate power that can be sold and therefore offset dirtier sources.
Whether wind and solar are built to offset thermal or nuclear plants, or to charge electric cars doesn't really matter. What matters is total load vs the sustainability of the average electricity generation source.
Companies like BC Hydro might not like the idea of storage at consumer’s side especially the one with solar panels. Probably they will push politicians to make laws to control its safety tightly.
I'm not party to BC Hydro's inner workings, but I certainly have the impression they are guilty of all the foot dragging they could get away with in terms of supporting wind, solar, run of river, and tidal. I could discuss what has happened in the last 10 years in that regard, but it has little to do with cars.
To summarize a few things:
- Hydro dams provide ideal buffering capability for the variability of wind and solar power. Hydro can also store excess thermal/nuclear generation, or provide a top-up for peak loads.
- There is no excess on-grid renewable/clean electricity generation capacity. It is all spoken for and used. Often at a premium.
- All new renewable/clean capacity either reduces the need for new thermal/dirty/nuclear capacity, or is used up by increasing demand.
- Therefore it can be said that any new load, such as charging electric cars, increases thermal/dirty/nuclear generation. Whether this is when there's excess capacity or not, due to the hydro buffering aspect.
- And so it may make sense to match demand for charging electric cars, to new electricity supply from conservation and new renewable/clean sources. You may choose between heating your driveway or driving your electric car, for instance.
- It may well be that powering cars with electricity generated by burning coal is more efficient than powering cars with gas engines, but I don't know.
- It makes no sense to take electricity and make hydrogen to make electricity to power cars. You lose efficiency at every conversion, and hydrogen is costly and dangerous to handle. That's why the promoters of this technology want the public to pay for a distribution system. It makes vastly more sense to just put the electricity straight into cars.
- It may well be that residential battery storage of electricity is viable. I suspect the money could be better put into solar, for instance. Would it be better than home generators? Interesting idea that needs to be evaluated.
- Private ICE cars are inherently one of the most inefficient means of getting people about. It's a system that's bleeding our society dry with massive and varied costs. It may have made sense when it was set up, and the downsides could hardly have been foreseen, but the problems are very apparent now.