Translate the total emissions that are believed “sustainable” into a per capita budget. In the case of carbon emissions, to achieve 450 to 550 ppm global average CO2 concentrations would allow emissions of 1 to 2 kilograms of carbon per person per day (kg C/p-d) by the year 2100 with an expected population of about 8.5 billion people—the latest UN population projection. Compare this to the current global average of 3 kg C/p-day and the U.S. average of around 17 kg C/p-d. Of course various http://sandsand.site90.net sources of energy have different implications, with electricity from coal emitting roughly twice that derived from natural gas. Hydropower is closer to carbon neutral, although there are some emissions related to the development and maintenance of hydropower electricity sources. Solar photovoltaic can also be close to zero on a life cycle basis. Calculate the portion of total emissions attributable to buildings. http://stroitel.net16.net
