We Should Drive EVs To Use Extra Electricity Capacity

We Should Drive EVs To Use Extra Electricity Capacity

Dr. Art Hunter, Canadian COR Board of Directors, shared a link into a CACOR discussion group.

https://cleantechnica.com/2020/05/14/we-should-drive-evs-to-use-extra-electricity-capacity/

 

Ian Whyte replied:

Hello Art, All:

It seems to me that it would make more sense to reduce capacity than figure out ways to use up ‘excess’ capacity.

Ian

 

Art Hunter replied:

Ian:

Yes, that is one option that makes sense but often is not totally practical.

Consider a nuclear reactor as a generating source.  It can take days to weeks to bring a reactor online from a cold start and an equal number of days to do a controlled shutdown.   This is why nuclear is often set as a base load generating source.   They can’t be turned up and down to meet demand.   They are ON or OFF.

Solar as a source is another possibility.   When the sun shines, power is generated and the intermittent nature of its power means storage or other means to time shift demand.  The cost of existing solar infrastructure has to be paid even if the energy is NOT used.  However, this energy can simply “not be used” and will adjust to the demand load.  The economics of this is not attractive.

Wind is a little different in that each windmill generator is typically ON or OFF when the wind is blowing.   So, like solar there is some ability to manage power output in increments of each windmill.   The invested infrastructure costs sitting unused is an issue.

Hydro is good for turning one or more of several turbines off and on with hours of warning and preparation.    Eventually water will “spill over the top of the dam” and go unused if in the OFF mode for too long.   Invested infrastructure costs sitting idle is the issue.

Thermal plants (coal) are also difficult to turn ON and OFF so are used as base load like nuclear.

Gas turbines are ideally suited to rapid ON and OFF demands but like to run at a constant speed so many of them make for step wise demand followers.

The utilities use their own methods to buy and sell power from neighbours to smooth over some of the swings in demand.  In fact they will buy and sell power in time blocks as small as 5 minutes and as low as 1 MW in size.   They also have the ability to adjust the voltage and change the frequency of the delivered power to meet demand variations in very small time increments like seconds.

In Ontario there is a mixture of all the above (except coal) so there is a lot of management activity to keep the lights on with a constantly varying load.   This management is a base cost no matter how many generators are operational.

The article was written with these constraints.  Hence, charging EVs is a good way to use existing excess generating capacity while reducing the number of fossil fueled vehicles on the road.   The baseline costs and invested infrastructure still need to be addressed.  Sitting idle is not good economics when excess power can be used to charge EVs.

Yes, not all power utilities are fossil fuel free but some are while others are transitioning.