If you haven't seen it yet, you might want to read Scientific American's strategy for a massive solar roll-out that would take place over the next four decades.
On the following pages we present a grand plan that could provide 69 percent of the U.S.’s electricity and 35 percent of its total energy (which includes transportation) with solar power by 2050. We project that this energy could be sold to consumers at rates equivalent to today’s rates for conventional power sources, about five cents per kilowatt-hour (kWh)....I appreciate the ambition and scale of investment and resources that this article is willing to contemplate and it is certainly a considered and well-researched piece. The strategy is laid out essentially as follows:
...The federal government would have to invest more than $400 billion over the next 40 years to complete the 2050 plan...The infrastructure would displace 300 large coal-fired power plants and 300 more large natural gas plants...The plan would effectively eliminate all imported oil...In 2050 U.S. carbon dioxide emissions would be 62 percent below 2005 levels, putting a major brake on global warming.
- CSP and PV are both brought to large-scale deployment by 2020, amounting to 84 GW (I assume actual installed capacity). This ramp-up stimulates manufacturer scale up, optimizing production, improving installation and reducing overall cost of solar drastically.
- Thin film cadmium telluride solar accounts for 80% of the solar energy, with module efficiency improvements to 14%, and $1.20/watt installation cost. Concentrated solar power with molten salt heat retention is further developed and accounts for 20% of solar power.
- In parallel, a new high-voltage, direct-current (HVDC) power transmission backbone is built from the US Southwest around the nation while compressed air storage facilities are installed around the country in abandoned underground facilities. Excess solar power would be sent over high-voltage DC transmission lines to compressed-air storage facilities throughout the country.
Federal policy support through 2020 includes loan guarantees, guaranteed government PPA, and price subsidies. After 2020, the study assumes self-sustained industry growth.
- In addition, over the next 40 years, a total of 46,000 square miles of easily available and accessible land will be required for photovoltaic and concentrated solar power installations.
Meanwhile, the total cost of this plan is sizable: $420 billion in federal government support over the next four decades, but the authors believe this to be a bargain:
Although $420 billion is substantial, the annual expense would be less than the current U.S. Farm Price Support program. It is also less than the tax subsidies that have been levied to build the country’s high-speed telecommunications infrastructure over the past 35 years. And it frees the U.S. from policy and budget issues driven by international energy conflicts.Certainly there are a number of aggressive assumptions and challenges associated with this plan. In fact, I feel it actually best serves as a “thought exercise”, as the article itself concludes:
The greatest obstacle to implementing a renewable U.S. energy system is not technology or money, however. It is the lack of public awareness that solar power is a practical alternative—and one that can fuel transportation as well. Forward-looking thinkers should try to inspire U.S. citizens, and their political and scientific leaders, about solar power’s incredible potential. Once Americans realize that potential, we believe the desire for energy self-sufficiency and the need to reduce carbon dioxide emissions will prompt them to adopt a national solar plan.UPDATE: There was one other thing I wanted to add to this post. The greatest benefit of this type of plan might not actually involve developments of solar energy per se but where that technology leads. While it's not the most efficient or cost-effective, $420 billion in federal expenditures can lead (indirectly) to a lot of R&D. I'm reminded of NASA's impact on technology transfer (e.g. fiberglass, breathing apparatus, GPS, computers, etc.) There's a great report on this here: "NASA’s Legacy of Technology Transfer and Prospects for Future Benefits"