Offshore wind is likely the best yield target for boosting our power grid in today's economy.
However, our sources of energy production are driven by market forces. Fossil fuels are simply cheaper. Governmental incentives to produce more "renewable" energy (no such scientific thing, but that's not particularly relevant to the topic) are a big challenge. R&D grants, etc., are of limited efficacy. A good way to have a lot of wasted money is to fund a project through a grant source. Increased regulation & taxation on fossil fuels if it is enough to artificially make the cost of fossil fuel energy production higher than renewable sources would do the trick. I'm uncertain of how that would impact our economy or the taxpayer, or if it's even necessary anyway. It's no surprise that more homogenous, less and more stable populous, more centralized and socialized, more socially progressive states with already high taxation and regulation are leading the way in these efforts.
I feel quite assured that, if costs of renewable energy go down or costs of obtaining fossil fuel sources go up, our production of renewable energy will be easily scaled.
Therefore, the argument for renewable energy at this junction is environmental. It's a good argument.
Other notes:
1. Fossil fuels are so much easier to store than anything else. For transportation fuels, this is of enormous importance. For electricity generation, it's still pretty important. Renewable sources are not necessarily easy to scale or predictable production sources. There is massive hourly and seasonal variation in electricity demand.
2. Hydrogen is not the answer. While there are many who are pursuing technological advances, it is never going to be particularly cheap. It is not mined from the ground. You have to produce a highly volatile gas and safely compress it and store it. While it's possible (and is currently a billion dollar industry) to produce a compact, clean, high-efficiency power product, it is never going to be easy. Also keep in mind that it requires a lot of energy to produce. It is not an energy source so much as a storage medium, and it's a poorly efficient one.
3. Electric vehicle technology is getting better. If we new oil was disappearing in 5 years, we could at this juncture replace oil as a transportation fuel. It would be more expensive and have significant limitations, but it is reasonably cost effective. As a current consumer technology, it is only artificially practical (producers lose money on these cars, and consumers only get savings through government subsidy). From an environmental standpoint, it is only as clean as the source of energy it is being charged with (in many places, electric vehicles are worse for the environment), and that's not counting the carbon footprint of the cost to produce. Battery capacity and efficiency are not likely going to make huge strides, but the ability to quickly charge batteries and/or quickly replace them mitigate this hugely.
4. In reference to #3, the gap here is maybe in the supply chain. Increasing costs of transporting goods could be really bad for the consumer. Maybe we could somewhat un-fubar our agricultural system if it were more financially important to source food locally, but I suspect transportation of goods to need to be much more expensive for that to happen. It would be much more destructive to other industries.
5. There is still plenty of oil. The rising costs of foreign oil sure spurred us into action for our local production. Without touching our oil reserves, we have the capacity currently to produce oil at lower cost than we were paying foreign oil in the recent past. Before that, peak oil, etc. caused plenty of concern and actions to investigate alternate energy sources and methods of increasing our own supply. However, not a whole lot happened until market forces made it profitable for us to use new methods of producing oil. Magically afterward, OPEC has driven down costs in an attempt to shut down our new oil production. Sadly, it has hurt many Americans who suddenly had new jobs, but our economy is a lot more diverse than oil production. And it's not like that prevents us from getting more oil in the future if it's cost effective. If anything, it helps our capacity because it provided incentive for our oil producers to become more cost efficient.