If you attend enough cleantech events or are pitched by enough startups, you start to see the same few PowerPoint slides over and over again. Here is a collection of the best or at least the most notorious and historically significant slides in our industry. This collection has been one of our most popular pieces and I'm taking the opportunity to update some of the charts and add some additional commentary.

After publishing this list to an overwhelming response, we heard from the original architects of some of these iconic greentech slides and we made sure to give them their overdue credit.  


From the BP Statistical Review of World Energy -- here's a painful reminder of what we pay at the pump. It's a chart of Crude Oil Prices From 1861 to 2010.



Make sure to contrast that with the Price Trends in Solar Modules in this slide with data from IPCC and Paula Mints of Navigant.  We've gone from $60 per watt to $1.50 per watt. What will it be in 2020?



Lawrence Livemore's classic Energy Flowchart:  A good slide provides a wealth of information in an intuitive, understandable way -- and this slide certainly does that.  This one slide shows energy inputs and outputs and really drives home the tiny foothold that renewables have in the American energy mix.

By the way, Americans are using less total energy and more renewable energy, according to LLNL.  The U.S. used less coal, petroleum, and natural gas in 2009 than in 2008, and increased its use of wind, solar, hydro and geothermal, according to the LLNL energy flow charts.  This probably has as much to do with reduced economic activity as it does a shift in energy sources.


EPRI's Prism Chart.  EPRI, the Electric Power Research Institute, is almost entirely funded by incumbent power companies, so their information has to be viewed through that lens.  Nevertheless, the "Prism" slide has found its way into many greentech presentations, mine included.  It conveys the challenge involved in reducing CO2 emissions from the electric sector down to 1990 levels.  According to EPRI, this task will require significant amounts of CCS (Carbon Capture and Sequestration), as well as another 64 gigawatts of nuclear power by 2030.


Carbon Wedges.  Princeton's Carbon Mitigation Initiative and the NRDC can both play the EPRI CO2 reduction game, as well.  The NRDC, though, does it without the nuclear wedge.



The Keeling Curve.  Regardless of the flaws of An Inconvenient Truth, the movie, or those of Al Gore, the man, the movie and the man present this CO2 data in a variety of compelling ways.  The graph shows the variation in concentration of  CO2 in the atmosphere over the last fifty years based on Charles Keeling's measurements at the Mauna Loa Observatory in Hawaii. Even if you don't subscribe to the theory of anthropogenic global warming, this chart is pretty stark evidence that something is happening and it's happening fast.



This slide from the CEC illustrates the "Rosenfeld Effect." California's per-capita electricity consumption stayed flat while consumption in the rest of the U.S. went up.  Why? Largely because of the California Energy Commission leadership of Art Rosenfeld.  During his tenure, California instituted utility efficiency programs, appliance standards and building standards that saved the state billions of dollars, millions of kilowatt-hours, and avoided the building of a large number of power plants.  It's not all about high technology.

The wind power flying spaghetti monster. If you've ever attended an event pertaining to energy storage, it's not unheard of for every presenter to flash this one.  It's originally from a 2007 CAISO (California Independent System Operator) report on Integration of Renewable Resources and shows the scary variable nature of wind power.  It speaks volumes on the intermittent nature of wind and the challenges of integrating renewable energy onto the grid without energy storage or fossil-fuel backup.

This type of variability and ramp up / ramp down strikes fear in the heart of every ISO (Independent System Operator). Read what Jim Detmers, formerly of CAISO had to say here.


The solar variability slide is just as scary in terms of the ramp-up and ramp-down rate, with cloud cover causing voltage sags.  This slide makes the rounds and comes originally from Jay Apt and Aimee Curtright's Working Paper, "The Spectrum of Power from Utility-Scale Wind Farms and Solar Photovoltaic Arrays."




The McKinsey Efficiency Study "finds that the U.S. could reduce annual GHG emissions by as much as 3.0 gigatons in the mid-range case to 4.5 gigatons in the high range case by 2030. These reductions from reference case projections would bring U.S. emissions down 7 to 28 percent below 2005 levels, and could be made at a marginal cost less than $50 per ton, while maintaining comparable levels of consumer utility."

The thrust of the McKinsey study is that there are pollution reduction choices that can be achieved at “negative cost.”  This flies in the face of economic theory, which would have us believe that companies and consumers would not willingly pass up profits by making changes in lighting, fuel efficiency, industrial process improvements, etc.  Turns out consumers aren't always entirely rational.



NREL's solar cell efficiencies slide.  The slide that launched several hundred solar startups is also partially responsible for the great concentrating photovoltaic (CPV) scare of 2008.  It does show the lag between hero experiment efficiencies and real-world PV performance and must be included in every solar presentation -- by law.


There are a lot of complicated ways to graphically illustrate the consumer side of the smart grid. This concise slide is not one of them.  EPRI claims authorship of this one.


The cubic mile of oil. The world uses about 30 billion barrels of oil per year. That is 1.2 trillion gallons, which works out to just about 1 cubic mile of oil.

And another way of illustrating the same concept:

Image courtesy of IEEE Spectrum


This slide from the leading renewable energy utility PG&E of Northern California (by way of Nissan) shows that fast charging a plug-in electric vehicle places a load on the grid equivalent to the average peak summer load of a single home.  Except that these loads move around from place to place and charge up whenever they feel like it, in the middle of the day or the middle of the night.  It means that widespread EV usage can't happen without a smart grid vehicle infrastructure.


Germany has the same solar insolation as the U.S. state of Alaska. Yet Germany is the global leader in solar installations. Why is that?  Three words: policy, policy, policy.  Mr. Colin Murchie Director, Federal Government Affairs at SolarCity and performer at Washington Improv Theater, originally produced this slide for SEIA.



Khosla Ventures' green portfolio.  This slide was immensely improved when the VC firm got a new graphic designer and got rid of the light bulb design.  In any case, it shows what you can do if you have a grand vision, sizable cojones and several billion dollars of your own and other people's money. And time for board meetings -- lots of board meetings.  The slide lists 40+ green startups, intelligently parsed, and we would bet there are a few more not being shown. One of these might be the black swan.  Vinod only has to be right one time out of ten or twenty to reinforce his genius status.



Bonus shameless self-promotion slide: Downloaded tens of thousands of times, this slide from Greentech Media's smart grid analysts smartly lays out the layers and players in the smart grid ecosystem:


And a final word on PowerPoint from Mr. Tufte:



Michael Kanellos contributed to this article.  Actually, he thought up the title and then went on vacation.