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Energy, Environment and Economy
Course Coordinators:
Pawel Keblinski, MSE
Lois Peters, Lally
Course Website:
http://homepages.rpi.edu/~keblip/ENERGYECONOMY/
Course Objectives
1. To introduce the complexity of the energy issue with its interdependencies between physical limits, market responses, environmental impacts, policy and law.
2. To develop project, research proposal, writing skills techniques for R&D and business related applications.
Course Structure and Grading
1. A series of lecture sessions by academics, industry and government representatives.
2. Energy related team project: 70% of the grade
Project presentation 30% Written document 40%
3. “Concept” exam: 15% of the grade4. Discussion participation: 15% of the grade.
Important Concepts I Wasn’t Taught in Business School
By Nate Hagens
Economic 'laws' were created during and based on a non-repeatable period of human history
The economy is a subset of the environment, not vice versa
Energy is almost everything
Cheap energy, not technology, has been the main driver of wealth and productivity
Energy is special, is non-substitutable in the production function, and has an upward sloping long term cost curve
Energy has costs in energy terms, which can differ significantly than dollar signals
Money/financial instruments are just markers for real capital
Our money is created by commercial banks out of thin air.
Important Concepts I Wasn’t Taught in Business School
Energy Consumption by Source (USA)EIA – Energy Information Agency (US government agency)
Age of wood Age of coal Age of
hydrocarbons
Energy is Everything as far as Macroeconomics is Concerned
Economic growth and energy consumption growth are strongly correlated
Germany vs. China
Germany appears to decouple economy and energy growth
But it is likely that it simply shifts energy intensive GDP to China
What if We Cannot Decouple Energy and GDP Growth?
We are at the peak of the fossil fuel mountainRenewables are our hope to stay on the top or for a gentle decent
Limits of Growth (1972 Book)
We must leave oil before it leaves us" Fatih Birol, Chief Economist EIA, 2008
G. M. Turnner, Global Environmental Change, Vol. 18, pp 397 (2008) “30 years of historical data compare favorably with key features of a business-as-usual scenario called the “standard run” scenario, which results in collapse of the global system midway through the 21st century. The data do not compare well with other scenarios involving comprehensive use of technology or stabilizing behaviour and policies.
Global ElectricityIEA 2013 Key Statistics
Coal is #1, oil is out, natural gas is in, other than hydro, renewables still small.
Energy Past, Presence, and FutureEconomist, February 10th 2001
Past is true – future is questionable, H is not an energy source but an energy carrier
The Biggest Push for Renewable Energy - Germany
Summer in Germany is good for solar and bad for conventional electricity generation
In the USA renewable are a lesser factor but utility companies already push to limit the ability to sell back to grid electricity generated by solar panels
In May 2014, during a sunny Sunday 74% of electricity was generated by renewable at the peak consumption
time
Renewable Energy Has Problems
Coal is still a king in Germany (hopefully not for long)
Vladimir Putin effect
The Central Problem - Intermittence
On monthly basis solar and wind complement each other and limit fluctuations to about factor of 2
On daily basis fluctuations are huge – a critical problem if
renewables are ever going to take the dominant position
Need for energy storage
But Fossil Fuels also Have a Problem: Peak OilThe rate of resource extraction increases,
peaks, and declines, assuming finite amount of resource.
M. King Hubbard predicted in 1950 that US production will peak ~ 1970 – he was ridiculed, but he
was right
Alaska
Shale oil
Energy Return on Energy Invested (EROEI)
€
EROEI =Usable Energy
Energy Expended
Wind and solar are OK
Fossil fuels were great, but are getting worse, as
extraction requires more energy
Biofuels are scam (think Iowa)
When EROEI = 1, the game is over, no matter what is the price. Actually, EROEI has to be > 3 run things (food + shelter, but not much more)
Net Energy
We will leave a lot of fossil fuels in the ground, once is takes too much energy to get them out, and perhaps, much sooner, if we are smart.
What We Need – How We Can Get It
Total World Power (all energy, 2013) ~ 15 Terra Watts (TW)
Solar flux near Earth - 1.37 kW/m2 is captured by πR2 area of the Earth shadow, and averaged over Earth surface area = 4πR2. Furthermore, about 50% of the flux is scattered or adsorbed before reaching Earth, thus effectively the flux per surface area is 174.7 W/m2.
The associated total power is P = 174.7 W/m2 x 4πR2 = 89,300 TW. This theoretical potential translates into ½ hour of sun providing 1 year energy use.
Extractable potential is about 60,000 TW due to theoretical (thermodynamic) limits on the energy conversion.
Technical potential is about 5,000 TW due to current technological limits (e.g., impracticality of over the ocean energy collection).
From solar FAQs by Jeff Tsao, Nate Lewis, and George Crabtree (Sandia NL)
What We are Currently Getting
Total World power (all energy, 2013) ~ 15 Terra Watts (TW)Total electric power ~ 2.5 TW
Solar capacity (2013) 136 Giga Watts (GW) but is characterized by 10-20% capacity factor proving ~ 20 GW, which is about 0.1% of the total and about 1% of the total electric power
Wind capacity (2013) 318 Giga Watts (GW) but is characterized by ~ 20% capacity factor proving ~ 60 GW, which is about 0.3% of the total and about 3% of the total electric power
Hydro provides ~ 0.4 TW, which ~ 16% electricity
The rest is from fossil fuels
Solar: Photosynthesis Efficiency
6H2O + 6CO2 + energy → C6H12O6 + 6O2
100% sunlight → non-bioavailable photons waste is 47%, leaving 53% (in the 400–700 nm range) → 30% of photons are lost due to incomplete absorption, leaving 37% (absorbed photon energy) → 24% is lost due to wavelength-mismatch degradation to 700 nm energy, leaving 28.2% (sunlight energy collected by chlorophyl) → 32% efficient conversion of ATP and NADPH to d-glucose, leaving 9% (collected as sugar) → 35–40% of sugar is recycled/consumed by the leaf in dark and photo-respiration, leaving 5.4% net leaf efficiency. Many plants lose much of the remaining energy on growing roots, leaving ~ 0.25% to 0.5% energy stored in the product (corn kernels, potato starch, etc.). Sugar cane is exceptional in several ways, yielding peak storage efficiencies of ~8%.
Solar: Ethanol
From corn, soybean and switch grasses is takes more fossil fuel energy input than the fuel output. Also it does not limit emissions – in other words is completely insane and alive only due to subsidies. US Gov. (DOE and DOA) claims it is not insane. Currently about ½ of US corn production goes to ethanol, and represents 3% of US liquid fuel consumption (by energy content), so even if it is not insane, it is not a solution.
From sugar cane it makes sense, yields several times more energy and 60% life cycle reduction of emission (US EPA classifies sugar cane ethanol as advanced biofuel). Brazil is the biggest player with ~20% of liquid fuel for transport coming from ethanol. However, it will not work in most places, and even in Brazil it is a partial solution.
Solar: Photovoltaics
Generate electric power by converting sunlight directly into electricity
Photons (light) excite electrons from the valence to the conduction band and can diffuse to the junction with other material leading to voltage. In related, photoelectric effect, excited electrons are ejected to vacuum.
Typical efficiency ~ 15%, can be as high as 40%, which is ~ 100 times better than ethanol.
Photovoltaics: Cost
The cost of the module is now smaller than other costs, such as installation, permits, etc.
From energy.goc
Concentrated Solar
Solar to heat, and then heat to electricity by a heat engine.
Typical efficiency ~ 30%. This number is a combination of increasing Carnot cycle efficiency with increasing temperature and increasing radiation losses with increasing temperature.
Cost ~ 0.1-0.2 $/kWh
Can be used with heat storage technologies to generate power overnight
What to do about a personal car?
Batteries – can we get the energy density required
Solar to fuel – hydrogen generation and storage
Biomass to fuel – sugar cane – yes, corn - no
Different Policy Approaches
Germany
No liquid and gas fuel resources
High taxes on liquid fuel
Still use a lot of coal (currently increasing)
Phasing out nuclear power
Approaching 30% electric power by renewable energy
USA
A lot of liquid and gas fuel resources with increasing production including shale gas/oil and ethanol
Low energy taxes
Coal on decline (and exported to Germany)
Solar picking up at selected states (California: Role of policy)
Wind provides 4% of electricity
Big questions
What will be the main drive for renewable energy
• Increasing cost of conventional energy• Peak oil
• Decreasing cost of renewable energy• Materials and efficiency• Installation cost, electric grid
• Policy associated with climate change/ national security
• Increasing taxes on energy or CO2
• Subsidies for renewable
What technical/scientific breakthroughs are needed• Energy storage, large scale for utilities and batteries/hydrogen storage
for transportation
Grid Storage Challenge (web comment)
It must be incredibly cheap. It must be efficient. It must be extremely long-lived. It must be reliable. It must have enormous scalability in both charging and discharge power to
many many megawatts. It must have enormous capacity in the hundreds of MW-hrs to GW-hrs range. It must be safe. One, two, maybe three of these. But the entire list? Exceedingly difficult. Not
something to realistically plan a wind/solar based power grid on, to be sure. But it would change everything, if it happens. I believe someone said in the last century that "What America needed was a
good five cent cigar." That never happened.
Storage: DOE Areas of Interest
Battery (electricity)Compressed air batteryCompressed air energy storageCryogenic energy storageFlywheel energy storageIce storage air conditioningMolten saltPower to gasThermal energy storageVanadium redox batteryLithium ion batterySuperconducting magnetic energy storagePumped-storage hydroelectricity – only significant player at the moment