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This assigment is due by 8 pm, Wednesday Nov 26

1. There are currently (as of Oct 2014) 395 parts per million of CO₂ in our atmosphere. In Oct 2000 the concentration of CO₂ was 367 ppm data source
   
   
   a) calculate the average growth rate in this period.
   
   b) at this growth rate what will the concentration of CO₂ in the year 2100.
   
   c) A reasonable approximation of the amount of surface temperature (in degrees C) increase as related to CO₂ concentration is given by:
   
   ΔT = 0.8 * ΔF
   
   where for CO₂
   
   ΔF = 5.35 * ln(C_now/C_before);   C_before = 280 ppm
   
   Using the result obtained in Part b, what is the predicted temperature change in the year 2100?
   
   c) Any values larger than +4C above our baseline temperature are considered as "dangerous".
   
   Over the last two years, CO₂ growth is occuring at a larger rate than the recent average. This rate is appoximately 0.75% per year and is likely to continue to accelerate. The US and China are the only relevant players in this acceleration which leads to the two scenarios below:
   
   
   
   
   Scenario 1: China is bombed back to the Stone Age so that only the US matters. Out to the year 2100 the US growth rate will be 0.9% per year as we burn our remaining coal and frack our remaining gas and continue to drive excessively.
   
   Under that scenario, what is the year that US only emissions drive us past the +4C mark?
   
   Scenario 2: US is bombed back to the Stone Age so that only China matters. Out to the year 2100 the China growth rate will be 1.4% per year as they feverishly emulate the US but at a much larger scale.
   
   Under that scenario, what is the year that Chinese only emissions drive us past the +4C mark?
   
   
   
   
2. Tesla's Powerwall Solution - let's do the energy math.
   
   Here is the raw data /technical specifications for this new product needed to solve all parts of this question.
   
   
   • 1 Powerall modular Storage = 10 KWHs
   • Continuous discharge power = 2KW
   • Battery Technology = Li-Ion @ 100 watt hours per kg.
   • Purchase + installation cost = $4000
   • Residential electricy rate = 0.1$ (10 cents) per KWH.
   • Typical residential rooftop PV array rated at 4 KW maximum output (=noon on a sunny day)
   • Average output in a day = 1/3 of peak
   • Rooftop cost + installation = $1.80 per peak watt.
   • Average number of suitably sunny days per year = 160.
   
   
   Show all work involved in making the following estimates:
   
   a) What is the weight of the 10 KWH modular storage unit and how many hours does it take to discharge?
   
   b) What are the up front costs to the homeowner for the purchase and installation of the storage unit and the PV rooftop?
   
   c) Averaged over the year, what is average daily available solar energy that can be used to charge up the powerall system?
   
   d) How many hours, given this average daily available solar power, would it take to fully charge the 10 KWH system?
   
   e) given your answer for d - explain what the homeowner would need to do to overcome this basic problem and estimate how much more this might cost.
   
   f) given d+e and the residential electricity rate described above, what is the approximate pay back time for just one of these storage modules?
   
   g) The Global Lithium Market - Refer to Exhibit 3 in that document. The Y-axis is in units of tons. Assume that 1/3 of world lithium production can be used to build Powerwall storage units for American houses. Using the 2017 projected data, approximately how many houses in america could have a Powerwall installed? What fraction of houses in America does this represent?
   
   h) Given what you know about scalability, write a 200 word newspaper editorial on whether or not the Powerwall is a scalable alternative energy solution for American houses.
   
   
   
   3. This tool will be needed for all of this exercise. (close the cover box that will appear in front of the map)
   
   
   a) From the select/deselect all panel at the bottom select only Power Plants and hit apply. In the upper right hand area there is a panel called "Data View: - select the bar graph icon. Note that clicking on any bar lets you drill down to the state level and clicking on those resultant bars drills down to the facility level.
   
   Emissions comparison: Here we will compare the 11 Western States with the industrialized MidWest. We define the latter region by the 6 States: WI,IL,IN,MI,MN,OH
   
   
   i) Determine the overall emissions for the 6 MidWestern States compared to the 11 Western states by summing up the values of the relevant individual states.
   
   ii) Determine the total populations in these two regions
   
   iii) Compare the per capita CO₂ emissions between these two areas and determine, from an inventory of the source emission the reasons why the Midwest is so much higher.
   
   iv) Using the Emission Range slider, identify and describe the 5 largest sources of emission in the US.
   
   
   b) A local newspaper has heralded Abengoa Bioenergy of Illinois as a Green beacon of hope due to its minimal greenhouse gas emissions. Everyone rejoices and joins hands in a circle around the facility and chants. Using the GHGRP data tool search function, determine their actual reported emissions from this facility. Put those emissions in context of emissions from a 500 MW Natural Gas Electricity Power Plant. (note: you will just have to hunt around for a 500 MW NG plant in the data).
   
   c) Note: You might have to exit the page and then enter it again to do this part. The interface is pretty klunky.
   
   Deselect all and then select only chemicals. From the drop down list on chemicals (upper right hand corner icon) delesect everything but amonnia production.
   
   Add up the three biggest contributors to ammonia production and report that number. Note, the units here are MT (metric tons) not MMT millions of metric tons.
   
   The amount of ammonia produced by these three sources could be used as a working fluid in a OTEC facility of nameplate power 10000 MW. The only GHG footprint of that facility would be the ammonia needed. Compare the amount of GHG emissions required for the ammonia production to the equivalent GHG emissions from 10000 MW worth of NG fired electricity.