Saturday, October 13, 2018

The Wild Texas Wind

If you are like most people, as long as you can plug something into the wall and turn it on, you don’t care much where the power comes from. But getting that power to your home or business is a complex process, which consists of all the power plants, transmission lines, and substations that go right to your electric meter, and everything else in between, aka, “the grid.”

Power is transmitted through the grid via alternating current (AC). If you don’t remember (or never had) high school physics, AC power reverses direction many times a second. In our country, that’s a frequency of 60 times a second. If the frequency changes too often and quickly, the grid becomes unstable and could crash. It’s analogous to water sloshing in a bucket. Slosh too much and you can’t keep the water in place.

Unlike other commodities, electricity, for the time being, cannot be stored in the quantities needed to meet fluctuating grid demand, although that issue is being addressed with rapidly developing technology. Power generators and utilities have to make sure that supply and demand are in balance at all times.

The grid in our country is not one big electric distribution system, it is actually three. The Eastern, Western and Texas Interconnections. These systems operate independently from each other.

So where am I going with all this?

One criticism I have gotten about my advocacy of large scale solar and wind is that because the wind doesn’t always blow and the sun doesn’t always shine, large scale alternative energy is not practical. The grid cannot handle the fluctuations. Critics tell me that above 11%, the grid will crash.

Is that assertion true? Actually – no. One of our grids routinely gets about 20% of its power from alternative sources. Which one? Texas. Texas the oil state is also Texas the wind state.

During 2017, 18% of the electricity provided to the Texas grid came from wind power. At times, wind was providing up to 45% of the grid’s power for hours at a time - and surprise, the grid did not crash.

According to a former official at the Oversight & Enforcement Division of the Texas Public Utility Commission, with whom I spoke earlier in the year, Texas manages wind power contributions to the grid with no significant issues. Wind will contribute more to their grid than coal by 2019.

There are still challenges getting wind and solar power integrated into the grid on a sustained basis, including development of sophisticated weather forecasting tools which can be used to predict how much wind and solar energy will be available at a given location, but these tools are being developed and prototyped right now.

In addition, according to the Department of Energy’s National Renewable Energy Laboratory (NREL) the Eastern Interconnection could accommodate up to 30% renewable energy with appropriate operating procedures.

Scaling up the technologies to add even more alternative energy to the grid is going to take time and investment, but there is no reason the US cannot accomplish this task, as long as there is the will to do it.

We are already switching to other sources of energy. Natural gas is filling this gap right now, slowly replacing aging and expensive coal and nuclear power generation facilities with gas turbine generators that can quickly increase or decrease contributions to the grid as needed.

As grid-scale battery storage technology continues to scale up, wind and solar power will be able to charge storage systems, eventually replacing many gas-fired plants which now handle local or regional grid fluctuations. Because natural gas is currently very inexpensive, the switchover will probably be driven by state mandates to decrease emissions.

Many states, Massachusetts among them, are now mandating ever increasing amounts of renewable energy to their power portfolio. Boston’s goal is 100% clean-energy sourced electricity by 2050. These mandates themselves will drive utilities to come up with plans to manage integration of alternative energy. Texas has already been taking this path and its grid operators and generators have responded.

Keeping the grid in balance has always been a matter of monitoring constantly changing demand. If grid operators could not manage this process, we would have blackouts all the time. They handle sudden power losses – such as transmission line failure or a sudden power plant shut downs without missing a beat, so they already have the know how to handle varying supply.

The idea that it is impossible to integrate large-scale wind and solar into the grid does not pass the laugh test, because Texas already does it.

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