Lecture 2 Make Sense of Energy Numbers

Gang He

August 29, 2022

NYC’s daily carbon dioxide emissions as one-tonne spheres

Climate stripes

Carbon budget

Emission and concentration

Get comfortable with units

Scale of numbers

Comparing the world’s energy resources

Energy stock and flow

Energy vs. power

Energy vs power

  • Energy is the ability to do work. Energy is power integrated over time.
  • Basic unit: joule = watt·second
  • Power is the rate at which work is done, or energy is transmitted.
  • Basic unit: watt = jourle/second

We need to know what we are talking about!

Back-of-the-envelope estimation

Art Rosenfeld

Rosenfeld Effect

Comparing with the Three Gorges Dam

Common sources of energy and climate data

- UN
- WB
- BP Statistical Review of World Energy


- CDIAC (Carbon Dioxide Information Analysis Center)
- EDGAR (emissions database for global atmospheric research system)
- Carbon Budget Project
- Carbon Monitor

Data quality

  • Availability
  • Accessibility
  • Credibility

Comparison, Validation, Verification

Use data tools

  • API
  • Packages
  • Open-souce tools

Big data and AI era

  • Big climate, earth, energy data available due to satellite, use-generated data, devices, sensors, smart meters
  • Data driven approches

Big data doesnot necessarily mean big picture

AI doesnot necessarily mean better insights


Fridley, David, Nina Z Khanna, Nan Zhou, and Michael McNeil. 2016. “Impacts of China’s 2010 to 2013 Mandatory Product Energy Efficiency Standards: A Retrospective and Prospective Look.” In. ACEEE. https://www.aceee.org/files/proceedings/2016/data/papers/5_131.pdf.
Hermann, Weston A. 2006. “Quantifying Global Exergy Resources.” Energy 31 (12): 1685–1702. https://www.sciencedirect.com/science/article/abs/pii/S0360544205001805.
Koomey, Jonathan, Hashem Akbari, Carl Blumstein, Marilyn Brown, Richard Brown, Chris Calwell, Sheryl Carter, et al. 2010. “Defining a Standard Metric for Electricity Savings.” Environmental Research Letters 5 (1): 014017. https://iopscience.iop.org/article/10.1088/1748-9326/5/1/014017.
Macknick, Jordan. 2011. “Energy and CO2 Emission Data Uncertainties.” Carbon Management 2 (2): 189–205. https://doi.org/10.4155/cmt.11.10.