Unlike solar and
wind (inverter-based) generation that must be changed into matching
waveform as conventional generation, the coal-fired plants require
large number of employees to keep plant operational, including welders,
bulldozer operators, trainloads of coal etc.
Offsetting job losses as
more renewables come on-line is the need for
grid
reliability ...
specifically to keep voltage "within ±10% of nominal at all points
across the grid." Keep in mind the grid is
cris-crossed over millions of square miles, with millions of
poles and transformers and customers ... comprising a system that might
not be fully mapped at the distribution level in 2021.
Read
The grid must hold
voltage steady. Voltage is the force that pushes amperage or current of
electrons across the wire. Even though power plants are interconnected,
each power plant can only energize a certain distance or area. If
several power plants go offline, then power must be shut off to some
customers so voltage levels can be maintained for remaining customers.
If voltage drops below nominal across the grid, then your 115 volt
refrigerator and 240 volt AC cannot run without damaging the motor.
Why? Volts and amps are inversely proportional. If volts drop, then
loads will draw more amps. More amperage means more electrons are
moving through the matrix (atomic structure) of the conductor (wire).
More electrons means more resistance from the wire which causes
heat which overheats design parameters of motor ... but also affects
substation relays that will trip off ... and can affect power plant
generators that will automatically shut down to avoid damage.
Utility-size generation from renewables has a large footprint
(as does coal, oil and gas) that hinges on large-scale
land acquisition
usually located far from end users ... which requires further land
access to
build transmission lines to urban centers over objections by landowners
etc.
Read.
The less reliable
renewables come with a "reduction in fault currents and short circuit
strength" ... meaning that "voltage support might be a vital ancillary
service to prevent voltage instability and ensure good power transfer."
Renewables require gas-fired generators that sit idle but come
online fast
when needed (viewed as uneconomical or impractical?) .... but also
require retrofitting the grid with
capacitor banks,
voltage
regulators, and
tap
changers ... and possible future innovations such as
massive batteries, compressed air storage,
solid
state transformers etc
read read2 read3 read4 read5 Resource:
Electrification magazine
Utilities
are challenged by aging networks ... challenged because grid updates
are expensive, labor-intensive and often dangerous ... challenged by economic
growth ...
challenged by changing resource
mix from solar and wind ... but also challenged by electric
vehicles that will try to replace the entire gasoline resource with
electric resource.
Read Read Read
The future will need .... new skills from labor ...
innovation using electronics that are more vulnerable to lightning,
solar storms and cyber attack ... changing standards to meet reliability goals
... protecting
appliances with voltage monitors that shut off appliance if voltage
drops ... all indicating that
considerable costs will be
passed onto customers ... and arguably
25% of the energy will be used to manufacture, retrofit and
maintain changes.
In my opinion, the
promise of 'lower costs' and
'money-saving' from renewables is not likely in the long run, and
ultimately less-reliable renewables will be an expensive way to
generate electricity
if the purpose is to supply power to everyone.
Read
