However, the uneven distribution of fossil fuel supplies among countries, and the critical need to widely access energy resources, has led to significant vulnerabilities.
[3] Energy security, therefore, has become fundamental from many perspectives, and is being therefore increasingly at the centre of legal and policy issues linked to social, economic, and development matters.
Biofuels from grain and beet in temperate regions have a role, but they are relatively expensive and their energy efficiency and carbon dioxide savings, vary.
Dedicated energy crops, such as switchgrass, are also promising cellulose sources that can be produced in many regions of the United States.
[9] In many warmer climates, a solar heating system can provide a very high percentage (50 to 75%) of domestic hot water energy.
The deployment of renewable technologies usually increases the diversity of electricity sources and, through local generation, contributes to the flexibility of the system and its resistance to central shocks.
[1] Renewable electricity supply in the 20-50+% penetration range has already been implemented in several European systems, albeit in the context of an integrated European grid system:[10] In 2010, four German states, totaling 10 million people, relied on wind power for 43–52% of their annual electricity needs.
[11] The Combined Power Plant, a project linking 36 wind, solar, biomass, and hydroelectric installations throughout Germany, has demonstrated that a combination of renewable sources and more-effective control can balance out short-term power fluctuations and provide reliable electricity with 100 percent renewable energy.
[12][13] It has been argued that investor-state dispute settlement rights may grant investors in carbon-intensive industries a mechanism to inhibit government policies promoting renewable energy technologies.