Ok so you had 3 points.
Moving parts wearing out. I take it you are talking of wind turbines. Firstly they are designed not to and are maintained. Obviously they don't last forever though. The uks oldest offshore wind farm was off the coast of blyth. It ran from 2000 till 2019. The old turbines were decommissioned and replaced with larger more efficient turbines. Onshore delaboe has been going since 1991.
How do we judge where it's going to be windy or sunny? Weather reports and surveys since 1835. You have to remember our electricity is connected to european countries. If it's not windy in the uk but is sunny in south of france we can top up with electricty from there, or draw from hydro power in norway, or wind in ireland. We are also investing in various forms of energy storage some that can be stored for centuries. When we have an over abundance we store it. When we need it we use it. This is what the uk is concentrating on now as our storage capacity is low. Also we still get energy from the sun if it's cloudy. Newer solar panels catch much more of the spectrum.
As for making it not being green. Not completely and it won't be till we have fully transitioned to clean energy. Only idiots from extinction rebellion expect this all to be done tomorrow. It is a process that takes time. But we are making strides towards it. Wind and solar on the surface are now cheaper than fossil fuels but energy storage is still expensive, but the price is coming down. Even so the price is competitive.
We are also looking at other types of clean energy such as geothermal. Drill a hole and tap the earths heat. We've been doing it for oil for over 100 years (we actually have a couple of plants in the uk) let alone the 23,000 disused coal mines in the country. No intermittency, no need for storage.
A report for the
Renewable Energy Association prepared by the engineering consultants
Sinclair Knight Merz in 2012
[28] identified the following key findings:
- The resource is widely spread around the UK with 'hotspots' in Cornwall, Weardale, Lake District, East Yorkshire, Lincolnshire, Cheshire, Worcester, Dorset, Hampshire, Northern Ireland and Scotland;
- Cost reduction potential is exceptionally high;
- Deep geothermal resources could provide 9.5GW of baseload renewable electricity – equivalent to nearly nine nuclear power stations – which could generate 20% of the UK's current annual electricity consumption;
- Deep geothermal resources could provide over 100GW of heat, which could supply sufficient heat to meet the space heating demand in the UK;
We already make heat pumps for shallow geothermal energy. That you have in your house instead of a boiler.
There's also biomass and others.
One last thing on energy storage. We have 300,000 evs on the road in the uk now (which will increase massively). More hybrids. Evs are basically battery packs on wheels.
Now we use our cars very rarely, for most of the time they are parked. We also have certain times of the day when energy demand is high. In the morning before we go to work and in the evening when everyones at home watching tv. These are the times cars are parked. The idea is for the cars to charge when demand is low, night time, or day time if there is a lot of solar energy in the country. Then feed back into the grid when demand is high. Owners of the grid will pay the owners of the vehichles for the electricity they use and motorists will get cheaper charging rates from charging when the cost of electricity is low.
Soon we will have millions of ev's, all the storage we need for any short term intermittency problems or fluctuations in demand. At no cost to energy providers or the consumer of energy.