Nuclear really is the only viable option at scale...
“Two terawatts of photovoltaic would require installing 100 square meters of 15-percent-efficient solar cells every second, second after second, for the next 25 years. (That’s about 1,200 square miles of solar cells a year, times 25 equals 30,000 square miles of photovoltaic cells.) Two terawatts of solar thermal? If it’s 30 percent efficient all told, we’ll need 50 square meters of highly reflective mirrors every second. (Some 600 square miles a year, times 25.) Two terawatts of biofuels? Something like 4 Olympic swimming pools of genetically engineered algae, installed every second. (About 61,000 square miles a year, times 25.) Two terawatts of wind? That’s a 300-foot-diameter wind turbine every 5 minutes. (Install 105,000 turbines a year in good wind locations, times 25.) Two terawatts of geothermal? Build three 100-megawatt steam turbines every day—1,095 a year, times 25. Three terawatts of new nuclear? That’s a 3-reactor, 3-gigawatt plant every week—52 a year, times 25.” Add it up, and when you’re done, you’ve got an area about the size of America—“Call it Renewistan,” says Griffith—covered with stuff dedicated to generating humanity’s energy."
That argument isn't even an argument. "Oooh, numbers are big and scary! Run away!"
The truth is that renewables (well, aside from biomass; that's usually what those arguments boil down to, so don't use biomass as your renewable source) scale just fine. The Earth is constantly struck by 100,000 terawatts of sunlight, and global primary energy demand is less than 20 terawatts.
Where do you put all the waste you generated covering renewistan with all the equipment and infrastructure you had to build??? Is that not an environmental disaster??? The environmental impact of all nuclear would be an order of magnitude smaller.
Where do we put the waste from industrial society in general? The material flow through the renewable energy system will still be but a fraction of the flow through the economy as a whole. The US makes 100 million tonnes of steel annually, for example. There is no need to use any toxic (or, really, uncommon) elements in renewables, so recycle what it makes sense to recycle and just landfill the rest. This is sustainable indefinitely.
In the very long term, humanity might face a problem with exposure of crustal rocks by mining operations. This causes reducing materials in the rocks to react with atmospheric oxygen, gradually depleting that oxygen. The long term solution to that will be to bury some reduced materials to compensate (the production of those materials released oxygen when oxides or CO2 were reduced). So, some level of sustained burial of waste material is not only acceptable, it's likely to be necessary.
“Two terawatts of photovoltaic would require installing 100 square meters of 15-percent-efficient solar cells every second, second after second, for the next 25 years. (That’s about 1,200 square miles of solar cells a year, times 25 equals 30,000 square miles of photovoltaic cells.) Two terawatts of solar thermal? If it’s 30 percent efficient all told, we’ll need 50 square meters of highly reflective mirrors every second. (Some 600 square miles a year, times 25.) Two terawatts of biofuels? Something like 4 Olympic swimming pools of genetically engineered algae, installed every second. (About 61,000 square miles a year, times 25.) Two terawatts of wind? That’s a 300-foot-diameter wind turbine every 5 minutes. (Install 105,000 turbines a year in good wind locations, times 25.) Two terawatts of geothermal? Build three 100-megawatt steam turbines every day—1,095 a year, times 25. Three terawatts of new nuclear? That’s a 3-reactor, 3-gigawatt plant every week—52 a year, times 25.” Add it up, and when you’re done, you’ve got an area about the size of America—“Call it Renewistan,” says Griffith—covered with stuff dedicated to generating humanity’s energy."
From the Whole Earth Catalog by stewart brand.