- The sun only shines so many hours a day and only certain latitudes are good candidates.
- Wind is quite noisy (sorry but it is, we've got a lot of wind here in Indiana that I've driven by going from Indy to Chicago. Absolutely not something I'd want near me. Much smaller scale vertical wind turbines are also quite loud and just plain annoying at higher speeds) and is ineffective at slow and high wind speeds, the wind also only blows at certain times.
- Hydroelectric generally requires dams, constructing dams often floods large areas of land which completely destroys ecosystems in that flooded land and often poses a considerable risk to downstream human settlements in the event of a catastrophic failure. They also rely heavily on obscene amounts of concrete which will build in a large amount of CO2 production into the construction.
- Hydroelectric relying on waves has varying level of impact on coastal ecosystems.
With sun and wind you can only implement it so far before you hit a wall, the wall being the need for huge amounts of grid storage to serve dark/not windy times.
Without drastic developments in battery technology, and PV efficiency, renewable aren't going to be a singular solution. They're going to remain a small percentage of the solution.
Renewables are also something that aren't really an option at a consumer level. You often have one power company that serves your home/apartment, if you do have a home and you live in an area where PV makes sense from a light availability then it is often more expensive than most people can afford and can take decades to be break even. Tesla announced something like $21.85 per square foot for their solar roof which comes to $43,700 for a 2,000 square foot home while in large parts of the country you can get a decent 2,000 square foot home for $100-200k and the median household income in the United States is only $63,688.
However adjusting your thermostat 1F warmer in the summer and 1F cooler in the winter, going to a local museum instead of taking that roadtrip or flight, eating hamburger once every other week instead of a few times a week etc are all far more practical changes people can implement in their lives than say installing PV and battery systems at their home or instead of buying an EV that costs thousands (if not tens of thousands) more than the ICE vehicle they'd otherwise purchase.
It's awesome, legitimately awesome, to pursue technology to help us solve the problem but thinking technology will be our savior is foolish at best. We have to radically change our lives if we want to even significantly slow those annual CO2 emissions. Food, clothing, recreation, convenience all needs to change.
It's not even that difficult. In the past year or so I've:
- Gone 90-95% whole food plant based with my eating
- Stopped going to the movies every other week and now only go for big films like the most recent Star Wars
- Stopped buying printed books if a digital copy is available for purchase
- Buy in bulk, with as little packaging as possible, when I can.
- Stopped driving 25-40 miles roundtrip every weekend to go sit in the living rooms of friends when we're just going to have the same conversations we do via text messages and instead only go see them once every couple of months each to eat together and actually have quality conversation
- Stopped driving to the fancy grocery 10 miles away and use the one a block from my apartment complex entrance, doing my groceries on the way home from work when I'm passing it anyway
- I pretty much only drive to work and church now instead of getting in my car on the weekend and driving around looking for something to do
- Video content I stream, I stream at lower quality now. Every gigabyte of data transfer saved is potentially several hundred of grams less CO2 generated. Podcasts, where available, I stream via their lower bitrate feed (unfortunately of the podcasts I listen to, only Mysterious Universe has a lower/higher quality feed).
If even 10% of the population adapted similar practices, you'd create much more of an impact than selling a few solar roofs to the wealthy or designing a piece of software for a regional power plant to use to make some process a fraction of a percent more efficient.