of unconventional oil and gas (e.g., oil sands, shale oil, tight oil, shale gas), or more on the use of non-fossil energy sources, like renewable energy. Total primary energy production from fossil fuels in the SRES outlooks range from a mere 50% increase from year 2010 in the B1 family to over 400% in the A1 family. Criticism Direct quote from abstract of Wang et al: Climate projections are based on emission scenarios. The emission scenarios used by the IPCC and by mainstream climate scientists are largely derived from the predicted demand for fossil fuels, and in our view take insufficient consideration of the constrained emissions that are likely due to the depletion of these fuels. This persistent problem has been criticized for a long time as many assumptions used for fossil fuel availability and future production have been optimistic at best and implausible at worst. The SRES and RCP scenarios have been criticized for being biased towards “exaggerated resource availability” and making “unrealistic expectations on future production outputs from fossil fuels. Energy cannot be seen as a limitless input to economic/climate models and remain disconnected from the physical and logistical realities of supply. A recent meta-analysis of the fossil energy outlooks used for climate change scenarios even identified a "return to coal hypothesis", as most mainstream climate scenarios foresee a significant increase in world coal production in the future. Patzek and Croft (2010, p. 3113) made a prediction of future coal production and carbon emissions. In their assessment, all but the lowest emission SRES scenarios projected far too high levels of future coal production and carbon emissions (Patzek and Croft, 2010, pp. 3113–3114). Similar results was reached by other long-term coal projections In a discussion paper, Aleklett (2007, p. 17) viewed SRES projections between the years 2020 and 2100 as “absolutely unrealistic”. In Aleklett's analysis, emissions from oil and gas were lower than all of the SRES projections, with emissions from coal much lower than the majority of SRES projections (Aleklett, 2007, p. 2). Select Committee report In 2005, the UK Parliament's House of Lords Economics Affairs Select Committee produced a report on the economics of climate change. As part of their inquiry, they took evidence on criticisms of the SRES. Among those who gave evidence to the Committee were Dr Ian Castles, a critic of the SRES scenarios, and Prof Nebojsa Nakicenovic, who co-edited the SRES. IPCC author