The ones you pick can make for very different energy economies.
For energy independence: Energy sources by country of origin.
True measure of gas concentration’s effect is radiative forcing – right scale.
Gas in better situation than oil given new extraction technology.Maybe there’s a lot more oil in places presently off limits like Atlantic & Pacific coasts, but not like Arabia.Constantly changing balance between rates of consumption and discovery.
Red – discoveriesOther colors – production of various sources.Don’t run out of oil, it just gets more expensive in both money and energy burden.From ASPO-USA.
Bullets of major changes since WWII, end of colonialism, end of Cold War, globalization
Industrial is only declining use. However, it was done by moving US manufacturing overseas, which doesn’t relieve USA of responsibility for China’s huge resource consumption and pollution problems.SUVs and bigger houses really took their toll since ~1990.
Petroleum is the biggest source while transportation is biggest sink.Big pairings:Petroleum to Transportation.Natural gas to Space & Process Heat for industrial, residential, commercial.Coal to Electric power.Renewable & Nuclear to Electric power.
Coal, and to lesser degree nuclear, have fueled electrical growth since WWII.Notice how renewable hydro was the big source of electrical generation before.Natural gas is picking up much of the capacity growth now.
The big culprits are oil in transportation and coal in electricity generation.
Coal & nuclear have high availability by ramp too slowly to follow load.Gas turbine can be dispatched to follow load.Sun-hour – Energy equivalent number of hours at peak sun, i.e. at panel rating.My 2,100W PV system average output is 448W
These numbers don’t include either components for practical system or conversion efficiency.Chemical fuels are best by far, and our lifestyle and expectations have been built by them!God gave us a great, but finite, gift to start the industrial revolution. Now we have a real challenge to maintain it.Hydrogen has the highest mass density, but carrying it in a small volume is extremely difficult.Electrochemical storage is 1/100 density of chemical fuel but continuing to improve and is boosted by much higher conversion efficiency.Ultracapacitor almost another two orders of magnitude worse.Ice is comparable to battery but a whole lot cheaper.Despite low energy density, thermal storage is cheap and easy for stationary storage.
Chemical fuel alternatives to petroleum, NG, and coal are going to consume a lot more energy.Corn ethanol and hydrogen by cracking methane are nonstarters.Solar and wind look very good counter to some early erroneous criticism.
Gasoline provided as comparison fuel.Can see why it’s so economical to recycle aluminum.Can understand the possibility that lightly-used rail might actually be worse for energy efficiency than buses on existing roads – an argument given against Denver’s Fastracks.These PV payback times are excellent compared to expected lifetimes of 25 – 40 years.
How fast can we collect or extract energy?
Among fuels, coal is bad while NG is a big improvement.
Heating buildings is more appropriate use of natural gas.
Questions about a Hydrogen Economy. By: Wald, Matthew L., Scientific American, 00368733, May2004, Vol. 290, Issue 5
Nissan says Leaf weighs about same as comparable gasoline compact, but it has batteries for 1/3 the range.
Tank to wheel performance as given by manufacturer’s EPA test compared to gasoline.Natural gas uses a little more (+4%) energy carrying heavy tank to save significant CO2 (-22%) due to higher hydrogen content of fuel.Hybrid is big improvement in energy and emissions (-42% for both).Hydrogen fuel cell uses about same energy (-12%) as hybrid but emits no CO2 because fuel contains no carbon.Electric is huge improvement in energy (-81%). Motor efficiency & regenerative braking far overcomes added battery weight.But tank to wheel doesn’t measure the full impact! Must look at the entire system – well to wheel!
Must look at how the vehicular fuel is manufactured and deliver and the energy consumed and CO2 emitted in the process.Electricity and hydrogen are energy carriers, not sources while their primary sources make big differences.Because extraction, refining, & delivery of petroleum and gas are so efficient, gasoline, NG, and hybrid vehicles don’t change their relationships.H2 fuel cell, even using electrolysis from the cleanest, most efficient conventional generators is the worst (worse than gasoline) in both respects.Plug hybrid becomes worse than combustion hybrid (38% worse for CO2) when charged with coal but remains better when charged with GCC.Electric from coal is better than gasoline in both respects but worse than hybrid in both respects, especially CO2.
Graphically making comparisons I just stated emphasizing need to analyze the complete energy pathway.Now let’s see where these number come from.
I’m assuming that gasoline is the energy source throughout the supply chain.
Used the highest efficiency of each type of generator.Coal emits 1.75x CO2 per unit energy as natural gas.For practical plants, coal CO2 emission is even worse at 2.6x.
Results depend a lot on source of electricity!Global warming: Worse than hybrid until electricity generated by more renewables.Independence and resources: Good. Makes any primary energy source useful for transportation. But can use more of that source.-------------------------------John Voelcker, “How Green is My Plug-IN?”, IEEE Spectrum, March, 2009.Plug hybrid charged from present US grid unconditionally beats 25 mpg gasoline car in CO2/mile, but it fails compared to non-plug hybrid (Prius, Insight) or high efficiency diesel.Plug-incompared to regular hybrid is more favorable than my analysis but still in same direction:Coal generation: 4 – 11% more GHGNatural gas combined-cycle generation: 25% less GHG
Using cleanest, most efficient conventional source of electricity (GCC) for electrolysis of water.The inefficiency of electrolysis plus energy consumed in compressing & transporting H2 compared to refining & transporting gasoline more than cancels the high efficiency of fuel cell & electric motor compared to ICE.
The big issue to solve for high penetration of renewables with their intermittent nature.
Summer: PV can handle a lot of the energy and reduce peak.Spring: PV peak encroaches on base generation that can adapt fast enough.
PV capacity quickly saturates and cost escalates at low share penetration because of this temporal mismatch.-------------------------------What is the parameter of these curves? Day/Night energy consumption?
Introducing concept of intermittency.First year of operation of my home solar PV system read at roughly weekly intervals with generation divided by 61% to match my annual consumption.Season mismatches readily apparent, but so are lots of weekly fluctuations.
Modeling wind & PV sources and loads distributed throughout US Western Grid.Geographic diversity can meet most of load with a little waste.Can almost eliminate deficit with 20% dispatchable gas turbine generation.How much better match with demand management, i.e. smart grid?
Smooth generation and load curves as they are offset in summer with AC.
Critics aren’t sincere when they say most Americans can’t afford to pay more for cleaner energy.Higher unit costs from cap & trade or carbon tax are intended to, and will, cause fewer units of energy to be used.Net energy expenditures will still rise, but not in proportion to unit costs, and most Americans can afford it.Benefits are indirect and hard to measure: lower taxes for defense, lower insurance for storms, lower food price increases.
Finally, I’ll discuss two drivers of energy consumption people won’t talk about: population growth & land usePer capita consumption, i.e. overall efficiency, has been level for nearly 40 years.Efficiency is balancing more uses, so let’s hold this constant.But population is growing steadily and rapidly.Population growth requires a huge wedge of renewables just to not increase greenhouse gases.But we want to reduce greenhouse gases, some government goals are 80% by 2050.It would be easier if we could invert the population wedge to add renewables to decrease carbon output.
Thinking About Energy PolicyEngineer Edition November 18, 2009 1 Peter M. O’Neill November 2009 Thinking About Energy Policy Peter M. O'Neill
Introduction November 18, 2009 2 This is a really complicated issue Solution possibilities change as technology changes Give you facts & tools to analyze these opportunities as technology and knowledge evolve. Put aside political passion for what technologically works Intended to be synopsis of half-day seminar Thinking About Energy Policy Peter M. O'Neill
Outline Policy objectives Understanding the problem Some principals Source to load analysis Temporal matching of source to load Source diversity: temporal & geographic Conclusions Skipping economics because it’s a huge topic by itself. November 18, 2009 3 Thinking About Energy Policy Peter M. O'Neill
Popular Energy Policy Objectives November 18, 2009 4 Thinking About Energy Policy Peter M. O'Neill
Objective:National energy independence November 18, 2009 5 Stop or avoid importing oil, (or future gas, uranium, …): To not depend on unstable or evil countries Reduce trade imbalance Thinking About Energy Policy Peter M. O'Neill
U.S. Oil Sources by Country November 18, 2009 6 Thinking About Energy Policy Peter M. O'Neill Although we are the third largest crude oil producer, most of the petroleum we use is imported. Western Hemisphere nations provide about half of our imported petroleum. Net imports have generally increased (58% in 2008) since 1985 while U.S. production fell and consumption grew.
Objective: Reduce global warming November 18, 2009 7 Reduce greenhouse gas emissions: To avoid effects at home. As moral imperative regarding rest of world being world’s 2nd largest emitter of GHG. Thinking About Energy Policy Peter M. O'Neill
GH Gas Concentration Trends November 18, 2009 8 Intergovernmental Panel on Climate Change 2007 Thinking About Energy Policy Peter M. O'Neill
Objective: Replace dwindling energy resources November 18, 2009 9 Fossil fuel is finite by nature - “Peak oil” Extraction harms environment Thinking About Energy Policy Peter M. O'Neill
Peak Oil November 18, 2009 10 Thinking About Energy Policy Peter M. O'Neill New oil fields harder to find, more expensive to produce. World demand continues to increase.
Understanding the Problem November 18, 2009 11 Thinking About Energy Policy Peter M. O'Neill
Why US & World At Critical Juncture Explosions in per capita consumption: Consumer products Transportation/mobility Urbanization/housing – more urban than rural Expansion of consumption to greater portion of world Every nation wants & is entitled to a good life. Planetary scale effects No unsettled or “undiscovered” land – all humanity in contact. Natural resources in any location accessible to people in any other location. But can’t maintain that other populations can’t use or aren’t entitled to resources in their lands. Human activity affecting composition of atmosphere & water Population explosion, 1950 -> 2009: USA – 152 -> 307 million World – 2.5 -> 6.8 billion November 18, 2009 12 Thinking About Energy Policy Peter M. O'Neill
U.S. Energy Consumption Trend November 18, 2009 13 Moved Industry Overseas Serious Conservation Thinking About Energy Policy Peter M. O'Neill
U.S. Energy Flows – 2008 November 18, 2009 14 Quadrillion BTU US Energy Info. Admin. – Annual Energy Review 2008 Thinking About Energy Policy Peter M. O'Neill
Electricity Sources November 18, 2009 15 Thinking About Energy Policy Peter M. O'Neill
U.S. CO2 Sources - 2008 November 18, 2009 16 Thinking About Energy Policy Peter M. O'Neill
SomePrincipals November 18, 2009 17 Thinking About Energy Policy Peter M. O'Neill
Capacity vs. Generation November 18, 2009 18 Capacity – maximum power plant can deliver. Determines capital cost Capacity installation gets attention but wrong measure of impact. Generation – energy plant can deliver over long time. Determines: Revenue Consumption & pollution from fossil fuels Fuel & pollution reduction from renewable sources Thinking About Energy Policy Peter M. O'Neill
Availability & Ramp Rate November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 19 All MW of capacity do not produce equivalent generation, hence fuel or CO2 savings.
Energy Source vs. Carrier November 18, 2009 20 Source Energy provided by nature either as we use it or from storage in geologic time. Sun – order of increasing time lag: Solar radiation Wind Biomass: wood, ethanol Fossil fuels: petroleum, gas, coal Nuclear material Carrier Medium for transporting energy from primary source to end use or for short term storage. Electricity Synthetic fuels: hydrogen, syngas Thinking About Energy Policy Peter M. O'Neill
Mass Energy Densities November 18, 2009 21 Thinking About Energy Policy Peter M. O'Neill Log scale! Electrical Thermal Chemical
Energy Burden November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 22 Takes energy to extract, refine, transport energy from primary source. Energy burden – ratio of energy consumed in the above to energy delivered.
Embodied Energy November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 23 Takes energy to build generation & transportation facilities. Leads to concept of energy payback time for generating facility.
Power Area Density November 18, 2009 24 Thinking About Energy Policy Peter M. O'Neill The problem with biofuels: Sun annual average flux, latitude 40º – 232 W/m2 Photosynthesis in switchgrass – 0.27 W/m2 , 0.12% efficiency. Photovoltaic at 15.5% - 36 W/m2 , 133x better Concentrating solar thermal @ 40% - 93 W/m2 Coal mine or oil field many times higher Fossil fuels store 10’s of millions of years of solar energy collected by inefficient photosynthesis. No way fossil fuel can last many centuries at current use rates. Would be great to capture & store sun’s energy through photochemical reaction that is much more efficient than natural photosynthesis. Bio-engineered algae? Photolytic reactor?
CO2 Emission Rates November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 25 Determined by ratio of carbon to hydrogen in the molecules.
The Cycle – Source to Load Analysis November 18, 2009 26 Thinking About Energy Policy Peter M. O'Neill
Internal Combustion Car – Motivations November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 27 All High energy density fuel for long range. Fast fueling. Simple technology. Low capital cost. Gasoline & Diesel Easy handling. Traditional availability. Natural gas Lower emissions. New US sources – shale & coal beds.
Electric Car – Motivations November 18, 2009 28 No emissions during use. Conversion efficiency Internal combustion engine – 25% Electric motor – 82%, 3.3x better Use electric storage to capture braking energy – Regenerative braking – Wheel to tank path. Create mobility from stationary primary energy source. Thinking About Energy Policy Peter M. O'Neill
Hybrid Gasoline/Electric Car – Motivations November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 29 “Combustion” Hybrid All energy comes from gasoline. Use electric storage to optimize ICE operation. Regenerative braking. “Plug” Hybrid Operate as, & with advantages of, electric car for short trips. Extend range with ICE.
Hydrogen Fuel Cell Car – Motivations November 18, 2009 30 Thinking About Energy Policy Peter M. O'Neill No emissions during use. Conversion efficiency Internal combustion engine – 25% Fuel cell (60%) × Electric motor (82%) – 49% Can make hydrogen from any primary energy source.
Representative Cars November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 31 Similar size cars.
Attraction of Transport Fuels – Tank to Wheel Analysis November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 32 Distance travelled from energy stored onboard.
Full Story – Well to Wheel Analysis November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 33 Distance travelled from primary energy source. Quite different!
Tank to Wheel / Well to Wheel November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 34
Gasoline & Hybrid Analyses November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 35
Electrical Generation to Vehicle November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 36 Renewable sources don’t directly emit net GHG so much better charging source.
Electric Car Analysis November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 37 Can manufacturer’s reported 5.3x MJ/km vs. 3.3x motor efficiency of electric to ICE be due entirely to regenerative braking?
Hydrogen Fuel Cell Car Analysis November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 38
Conclusions on Car Fuels Combustion/electric hybrid advances all 3 objectives. Hydrogen fuel cell present energy efficiency & CO2 emission worse than gasoline ICE. Only helps independence if cheap, plentiful stationary source available like nuclear was supposed to be. Must improve H2 generation, storage, transport. Electric can advance all 3 objectives. In exchange for cost & limited range. Better way to use NG for transport than CNG. Will make sense with more renewable generation. November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 39
It’s About Time – TemporalMatching of Source to Load November 18, 2009 40 Thinking About Energy Policy Peter M. O'Neill
Electricity Load Duration Curve Short duration demand peaks set system size. Demand response can reduce system size & same energy. November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 41 EPRI – “The Green Grid”
How Well Could PhotovoltaicsMatch Loads in Texas? Canyon Abilene Overton El Paso Austin Del Rio Corpus Christi Laredo Edinburg Courtesy of Walter Short, NREL Simulated 16 GW of PV generating 11% of load at 9 sites spread uniformly around Texas and compared generation with load Min base Load op. Surplus Spring Day Summer Day 42
How Well Could PhotovoltaicsMatch Loads in Texas? (2) Courtesy of Walter Short, NREL 43
Solar Generation Match to Load 1st year of operation of my PV system Rating: 2.1 kW Energy produced: 3,327 kWh Energy consumed: 5,493 kWh Read meters weekly November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 44
Stochastic Modeling of Source & Load Computation: Assume instantaneous match = net match over interval, i.e. some storage. Determine surplus or deficit at each weekly interval. Sum intervals over year. Net = TotalPVGen/TotalLoad Load Met = 1-TotalDeficit/TotalLoad Observations: Sized to use all I produce Make large surpluses to avoid deficit Would be more dramatic with hourly data. November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 45
Source Diversity November 18, 2009 46 Thinking About Energy Policy Peter M. O'Neill Spatial & temporal diversity Wind blows different places at different times Sun can power evening loads to east Clouds are spotty Place sources closer to loads, reducing transmission loss Consequences Must connect renewable sources to grid Must build a lot more transmission Transmission will become more expensive because it will only be used intermittently More difficult to maintain grid stability
How Well Could Wind GenerationMatch Loads in the West? Courtesy of Walter Short, NREL Results from Optimizing Wind and PV Sites to Match Loads in the WECC Surplus Wind Shortfall In generation 47 80% Wind & PV Only Wind & PV
Storage for Temporal Load Offset November 18, 2009 48 Thinking About Energy Policy Peter M. O'Neill Ice Energy, Inc. ice storage air conditioning. Solves root cause of peak load problem. Thermal efficiency through non-cycling design & off peak consumption. Stores energy off-peak,dispatching it on-peak Predictable and measurable
Combined Heat & Power Where does waste energy in electrical generation go? Low temperature heat. What use is low temperature heat? Space, water, process heating. Solution Generate electricity in building that needs heating. But heat not always needed when electricity is. Freewatt® reciprocating engine Electricity: 1.2 kW, 26% Heat: 3.46 kW, 74% Close to my 23%/77% Elect./Heat Microturbine >75% efficient November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 49 Honda/ECR Freewatt Micro Combined Heat & Power example residential installation
Demand Management Electric utility model has been to vary generation to meet the load. Load has changed Higher peak to average with AC More is optional or deferrable: laundry, dishes, computer print & backup, landscape lights Renewable sources not as dispatchable or schedulable. Control & communication technology now enable better matching of intermittent loads to intermittent sources Smart Grid. Significant distributed storage possible: Domestic hot water Ice for air conditioning PHEV – do I want to donate my expensive battery cycles? November 18, 2009 Thinking About Energy Policy Peter M. O'Neill 50
Can Individuals Afford Clean Energy? November 18, 2009 51 Take my utility expenses 2 people, 2 cars, 2 cell phones Efficient house Live close to activities Count all electric as purchased from utility (ignore PV) Energy only 30% Discretionary > 32% A lot didn’t exist 20 years ago but has great use Could make room for substantial energy cost increase Wouldn’t get more use for it Would use less Thinking About Energy Policy Peter M. O'Neill
Population Growth November 18, 2009 52 310 Due to population growth 80% Reduction from today Thinking About Energy Policy Peter M. O'Neill
Meeting the Objectives Independence Replace oil for transport with gas, electric not from oil. Global Warming Replace coal for electric generation with nuclear, wind, solar. Replace oil for transport with gas, electric after replacing coal generation. Resource Depletion Nuclear electric with advanced breeder fuel cycle. Wind & solar electric. Electric transport. Solar & electric geo-backed heat pump for space & process heat. All Domestic renewables November 18, 2009 53 Thinking About Energy Policy Peter M. O'Neill