The Language of Energy

In order to have any kind of rational and meaningful conversation about energy generation, energy supplies, energy shortages, we must quantitatively understand the units of Energy.

Most of you are familiar with Power and you frequently confuse that with energy. For instance, if you have a 100 Watt light bulb and you plug it in, that light bulb radiates 100 Watts of Power . Power is instantaneous or, in other words, at any given time while the light bulb is on, it radiates 100 Watts of Power.

However, what we care about is Energy

ENERGY = POWER * TIME (of use)

Thus if we use our 100 watt light bulb for 1 hour we have used the equivalent of 100 watts * 1 hour = 100 watt hours of ENERGY.

For residential, commercial and industrial energy use, the standard metered rate used by all electrical utilites in the US is the KiloWatt Hour (KWH)

If we use our 100 Watt light bulb for 10 hours then that is 100 watts x 10 hours = 1000 watt hours = 1KWH.

Your electricity rate is charge at some number of cents per KWH.

Watts:

• 1000 Watts = 1 Kilowatt
• 1000 Kilowatts = 1 Megawatt
• 1000 Megawatts = 1 Gigawatt (GW)
• 1000 Gigawatts = 1 Terrawatt (TW)

• 1 TW = 1 million Megawatts

An Example of Scale:

Total US NET electricty consumption in the year 2013 was approximately 4000 Terrawatt Hours (TWH). We don't want to do these kinds of problems in energy units, but rather in power units.

There are 365 x 24 = 8760 hours per year.

So the NET electrical power requirements for the US are:

4000 TW hours/8760 hours = 0.457 TW or 457,000 Megawatts.

However, integrated over all sources of power generation, we are about 50% efficient meaning that 914,000 Megawatts (0.91 TW) of power was actually produced in order to use 457,000 Megawatts of electrical power.

Averaged over the entire United States, the typical power plant size for the generation of electricity is 300 MW (tho individually this ranges from 1 MW to 6000 MW). An example of the large range of individual power plant capacities can be seen for coal in the US.

Thus we have 914000/300 = 3050 or approximately 3000 individual powerplants that need to be hooked to the national grid for electricity production.

Note, also, for reasons to be discussed later, we are now annually losing about 10% of power plant generated electricity in our aging grid system.

This loss is equivalent to 300 power plants!

Clearly as our demand for electricity grows, we require more and more power plant construction. It is most cost effective to build a few large scale plants, rather than many smaller ones, due to grid limitations.

We now show the evolution from 2007 to 2016 of state based residential rates for electricity in the US.

2007 Snapshot

2016 Snapshot

It is useful to compare OR to other states like CA, NY and TX.



Notes:

• There are no longer strong state to state variations in the cost of electricity as existed in the past (15 years ago or so)

• Regionally, the Northeast Pays 1.5 times more than the national average so energy costs are a significant political and social concern there.

• The Pacific Northwest no longer has a sole monopoly on cheap electricity. Some of this is related to long term climate change which is causing a significantly reduced snow pack and therefore reduced hydroelectricity as part of overall energy portfolio.
  
  
• Electricity prices in the state of Texas (now cheaper than OR) have come down largely due to significant capacity additions in Wind.
  
  Traditionally, hyrdo has provided about 70% of Oregon electrical power. However, due to reduced stream flow in the Columbia River Basin, hydro now has fallen below 1/2 and Oregon is not as green as you think it is:
  
  Oregon Electricy Mix averaged 2012-2014:
  
  
  
  Note that NG is still about 3 times higher than Wind, and solar is virtually absent. Since demand is rising and we are not going to have any increasing hydro power then, in Oregon, its really a contest between building out NG or building out more Wind in order to reduce Coal. Note also that much of the "Coal" (and all of the Nuclear) is coal fired electricity that is exported (from Washington, Wyoming, Nevada) into Oregon through BPA. Oregon is not really a state in this regard but rather is a a member of the BPA region.