Homework Question on Energy Analysis and Life-Cycle Assessment
- Read Chapter 5 of “Energy for Sustainability, Technology, Planning, and Policy” by John Randolph and Gilbert M. Masters
- Answer the following questions and submit them below:
- Why are the EROI values for U.S. ethanol fuel from corn different in the studies performed by Shapouri, et al. (2004), Pimentel and Patzek (2005), and Farrell, et al. (2006)? Explain in terms of input energy and co-product energy.
- Describe a case study of the analytical code PRISM developed at Princeton University. Include the company or institution using the software, what data was monitored, and how efficiency intervention was evaluated.
- Table 5.10 lists the average emission rates of CO2, SOx, NOx, and Hg for Washington, California, Virginia, and West Virginia.
- What 5 states have the highest emission rates?
- What modifications to the plants in these states are being made to lower emissions?
- Are new plants being built in these states to replace the high emitters?
Homework Answer on Energy Analysis and Life-Cycle Assessment
Energy Analysis and Life-Cycle Assessment.
The energy return on investments (EROI) on the production of ethanol fuel from corn have different figures due to the various assumptions made in values of direct products, co-products (are used as add in the energy production process) and the outputs .According to Pimentel and Patzek (2005), they argue that extracting ethanol fuel from corn will result to more costs than benefits.
They further noted that if the co-product value is larger than the output value, it will result to a negative efficiency value, that is, more energy is spent on the production process as compared to the resulting output. This makes the EROI margin to be far lower than as it would have been if specific measures were put on regulating the co-products input value to be .Their research further states that this scenario could have risen because of factors such as: use of outdated data in production process of ethanol fuel and the use of discounts in co-products .
To solve this, they advocated for an increase in input energy and providing no credit if co-products energy is required during energy generation( Isheden,2012).On the other hand, Farrell, et al. (2006), argued that the initial input of products can be increased while the co-product value is reduced, the resulting efficiency value will be more than the one obtained from Pimentel’s research .The efficiency value will be even higher if the co-product is treated as negative input.