Why should we care about energy?

Transcription

1 Why should we care about energy? Energy is the prime mover for the economy without abundant and cheap energy there is no economy Fossil reserves are fi nite, and we are burning through them fast Fossil reserves are not found uniformly around the world, and increasing demand creates geopolitical instability Consumption of fossil fuels is affecting the composition of the atmosphere and the climate

2 The good news Sustainable energy technology is improving by the day, and many technologies are becoming economically attractive. There is tremendous opportunity in many areas including R&D, design, manufacturing, economics, policy development and others. Sustainable energy has the potential of renewing the world's economic outlook. It's good for the planet and for future generations.

3 Energy and economy The human development index (HDI) measures standard of living HDI goes up with energy consumption, but with diminishing returns > 50 GJ/year/capita of energy use produces a good standard of living Energy consumption of human body at rest: 100W or 3.15 GJ / year

4 HDI around the world

5 The fi nite nature of fossil reserves Underlying global demand for energy by 2050 could triple from its 2000 level if emerging economies follow historical patterns of development. Ordinary rates of supply growth -taking into account technological, geological, competitive, fi nancial and political realities -- could naturally boost energy production by about 50%. This gap this Zone of Uncertainty will have to be bridged by some combination of extraordinary demand moderation and extraordinary production acceleration. So, we must ask: Is this a Zone of Extraordinary Opportunity or Extraordinary Misery?

6 Where is the oil? Proven reserves (conventional & unconventional). Ease of extraction depends on resource type.

7 Climate change I: CO2 emissions Some facts: Historically steady concentration 280ppm Concentration now ~380ppm Rapid increase from direct and indirect measurements starting in late 1700s 2000 emissions: 34 x 109 CO2 equivalent Anthropogenic CO2 emissions are increasing concentration

8 Climate change II: effect of CO2 CO2 is a greenhous gas Visible radiation from sun passes through atmosphere (mostly) and heats surface Infrared heat from surface absorbed by GHGs (CO2, CH4, N2O etc.) Effective emissivity of earth surface decreased higher temperatures needed to maintain equilibrium These effects can be measured, they are not an opinion

9 Climate change III: so what? Climate is a very complex and highly nonlinear system Strong interactions of atmosphere, ocean, biosphere Models are full of uncertainty: Clouds Ocean absorption Forest growth Ice sheets & shelves Most models predict a 2ºC average increase in surface temperature with a doubling of CO2

10 Possible consequences

11 Possible consequences Nutrient availability shifts in coastal upwelling zones Zones of depleted oxygen (dead zones) become larger and longer-lasting Shifts occur in the geographic ranges and die-off rates of some ocean species Corals and mollusks experience declining calcifi cation rates and corals exhibit more frequent bleaching events

12 Possible consequences Average area burned by wildfi re per year in parts of western United States increases by two to four times per degree of warming Decrease of fi re risk in grasslands, which may wither into deserts Disturbances arise from changes in the frequency and timing of fi re, pests, and disease Predictions of fi re risk are diffi cult because they do not yet account for feedback in ecosystem Detailed predictions of rainfall at the local level also diffi cult

13 And more... Decrease in annual runoff Increase in severe precipitation events Heat-related deaths increase, cold-related deaths drop Insect-borne diseases shift location Respiratory illnesses, asthma increase Increased risk of water contamination Sea level rise impacts coastal communities Damage from severe weather increases and many others

14 Is energy the real problem? Energy is not the only emitter, but certainly it is the biggest.

15 Who's responsible?

16 Historical emissions

17 Factual assertions: global fossil-fuel burning emits 34 billion tons of carbon dioxide equivalent per year; if CO2 concentrations are doubled then average temperatures will increase by C in the next 100 years; a temperature rise of 2 C would cause the Greenland ice cap to melt within 500 years; the complete melting of the Greenland ice cap would cause a 7-meter sea-level rise. Answering these is a scientific question they are either true or false, more or less likely, etc.

18 Ethical assertions: it s wrong to exploit global resources in a way that imposes signifi cant costs on future generations; polluting should not be free; we should take steps to ensure that it s unlikely that CO2 concentrations will double; politicians should agree to a cap on CO2 emissions; countries with the biggest CO2 emissions over the last century have a duty to lead action on climate change. The answer to these questions is not either true nor false it depends on our values or judgement best left to politicians?

19 The mother of all ethical assertions Sustainable development should meet the needs of the present without compromising the ability of future generations to meet their own needs What is a need anyway? How many generations in the future do we care about? What about population growth? Should we just go back to subsistence farming?

20 The macro energy budget Total quads (1015 Btu) or 29.2 x 1012 kwh

21 The micro energy budget Food Shelter (heating & cooling) Lighting Transportation - local Transportation long distance Stuff (appliances, computers, toys etc.) Transporting stuff Powering gadgets Defense Total (for a Brit) 195 kwh / day

22 So what is a kwh? One kwh is a power of 1000 W exerted over one hour An average fi t person on a bicycle can output ~150 W To generate 195 kwh of energy, this average person would have to pedal for 1300 hours (over 54 days, 24 hours per day)

23 How much do we pay energy guy? Minimum wage in NM: $7.50/hour Cost of 1300 hours with no overtime: $9,750 What we would pay to the electric company if we bought all the energy from them: $0.1018/kWh x 195 kwh = $19.85 Thank you fossil fuels!

24 Recommended reading MacKay: Sustainable Energy Without the Hot Air, chapter 1 Shell International BV, Shell Energy Scenarios to An era of volatile transitions Australian Academy of Science: The Science of Climate Change Questions and Answers National Research Council: America's Climate Choices National Research Council: Warming World Impacts by Degree