What happens to all the dead electric-car batteries?
Batteries are, thankfully, a longer time horizon problem.  In my opinion the real question is about power generation.  Unless we get serious about fast-tracking next-generation nuclear, I don&#x27;t think we can support a massive deployment of electric vehicles.  Or, put a different way, the electricity will have to be generated by burning even more coal than the baseline.  Wind and hydro are not an option, as there&#x27;s a strong limit function on expanding capacity.  While solar sounds great it has its own set of issues, including a narrow generation region (both geographical and time-of-day) that would require a massive deployment of batteries to even out.  This, in turn, would also require a hard look at the environmental effects caused by the manufacturing of these technologies at scale.<p>And then there&#x27;s the question of energy conversion efficiency.  Let&#x27;s start from the principle that all conversion of energy happens at &lt; 100% efficiency.  A switching power supply of automotive class is likely in the 85% efficient, maybe less.  Power generation itself is less than 100% efficient.  And, finally, charging isn&#x27;t 100% efficient.<p>Efficiency math for a chain of devices is simple, just multiply the efficiencies of each device in the chain to obtain the system efficiency.<p>If power generation efficiency is 80%; charger station another 80% and battery charging (the battery stores less than 100% of the energy that goes into it) 80%, the total system efficiency is 0.8 x 0.8 x 0.8 = 0.5 or 50%.  Yikes!<p>In other words, HALF the energy used to charge an electric vehicle is wasted, likely as heat.  That&#x27;s assuming it is a three step process.<p>The truth is there are additional links in the chain.  For example, the transmission of electricity though power lines and transformers isn&#x27;t 100% efficient.  In California we are at about 90% [0].  This would bring my prior estimate down to about 45%.<p>I would not be surprised if a full accounting of losses, from generation to energy stored in a battery, is in the 30% range.  From that to energy-in-battery to energy delivered to the wheels is a different matter.  Maybe 90%?<p>I haven&#x27;t seen a study analyzing the realities of mass electric vehicle deployment from an energy efficiency perspective.  Does such a study exist?<p>EDIT:
The real question needs to look at deployment at scale.  We have about 300 million vehicles in the US.  Assuming all of them are replaced with electrics and accounting for generation-to-wheel losses, how much new energy generation would we require?  Other than burning coal and natural gas, how do we get there?  I suspect electrics are not even close to being as &quot;green&quot; as people think they are.  They sure feel good because, locally, in front of your own eyes, they feel clean.  However, the real evaluation has to take into account the entire system.<p>[0] <a href="http:&#x2F;&#x2F;insideenergy.org&#x2F;2015&#x2F;11&#x2F;06&#x2F;lost-in-transmission-how-much-electricity-disappears-between-a-power-plant-and-your-plug&#x2F;" rel="nofollow">http:&#x2F;&#x2F;insideenergy.org&#x2F;2015&#x2F;11&#x2F;06&#x2F;lost-in-transmission-how-...</a>