1) Very few middle to large cities can be powered by solar or wind. Not only is there not room to install such energy devices but they're not powerful enough. Could you imagine how large a wind turbine farm would need to be to power New York City? Same issue with solar power, it would take too many panels and too much space to handle large populations. Good luck finding legitimate research that shows how a dense population with limited land, can support these alternative energy sources.
Power plants in general can only generate so much power so they only have so much reach; meaning the end-users need to be within the power grid. The first Edison plant served just 100 homes in NYC. This means that the land needed for wind or solar would need to be close to NYC and it would need to be massive. The best report I found supporting alternative energy, showed that it could handle only 10% of current energy consumption in New York City. Places like Los Angeles would be far worse because of how spread out the city is. The further away the alternative energy plants are located, the more difficult it is for them to generate enough power to meet demand.
2) Wind turbines of course require wind, which isn't always consistent especially in some places around our country. People are spoiled these days and aren't used to outages so not only would it negatively impact our conveniences, it can also be dangerous as well. Generators would become even more common and they won't be powered by wind or solar. Not only is there not enough wind in some areas around the country, many places in states like Ohio, don't have the level of solar energy necessary because they don't have as many sunny days as other parts of our country.
There are some states that could do a decent job of getting by with wind and/or solar, but it's not a fix for our entire country. If you listen to some of these liberals, you wouldn't think this was the case. They're making promises they know they can't deliver on but they don't care; they will always be able to blame other people for it not coming to fruition. Votes are always about the here and now.
The bottom line is that alternate energy sources are important to continue to develop, but for these politicians to make it sound like we can get away from nuclear power, oil, and gas, are lying. To say that we can make it happen in just ten years is crazy and so are the people who believe it.