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Four Takeaways from The Capx2050 Transmission Planning Report

One of the biggest issues for Minnesota’s electric grid is the topic of transmission lines. Transmission lines are expensive, and renewable energy sources, especially wind, require a lot more transmission lines than a grid powered by conventional generation resources like natural gas, coal, nuclear, and hydroelectric power.

The last round of transmission spending was called CapX2020, which built approximately 800 miles of transmission lines, at a cost of $2 billion, according to a story in the Star Tribune.

The transmission lines built as part of the CapX2020 are already full, so a new study called CapX2050 is being conducted to learn how Minnesota’s transmission system would need to evolve if we close our reliable, dispatchable coal-fired power plants and attempt to replace them with intermittent, weather-dependent resources like wind and solar.

The findings are startling, and should be an enormous red flag warning Minnesota lawmakers that more renewables are not a good idea. Here are the four key takeaways from the CapX2050 report:

Finding One:

“Dispatchable resources support the electric grid in ways that non-dispatchable resources presently cannot. They provide physical attributes that help maintain a stable and reliable grid. As dispatchable resources are retired, it will be essential that new and existing generation and transmission technologies are deployed with the ability to provide grid support in the appropriate locations to ensure reliability is maintained.”

This essentially means that coal, nuclear, and natural gas plants perform valuable functions to the grid that wind and solar cannot, and that a combination of old technology and new technology will be required to do the same job our current generation fleet already does well. This means will be spending extra money for potentially worse service.

Moreover, some of the technology needed to perform grid stabilizing functions in a world with more intermittent renewables doesn’t even exist yet. This means lawmakers who are pushing for more wind and solar on the grid are doing so despite the fact that they are creating a mandate with no technologically feasible way to accomplish the mandate, at this time.

Finding Two:

“Reliably meeting real-time operational demands will become more challenging than they have been in the past as dispatchable resources are retired and their corresponding ancillary services are lost.”

This means that it will become more difficult to provide reliable electricity, 24 hours per day, seven days per week, 365 days per year as we move away from our dispatchable coal fired power plants and try to rely more upon wind and solar power.

According to the report, renewables are weakening the transmission system, which means the transmission system is more vulnerable to problems, and that the wide variability of the output of non-dispatchable resources, even within a single day, create massive challenges that will require billions of dollars in additional transmission spending to help reduce the possibility of blackouts.

Finding Three: 

“To maintain reliability of the system as we integrate more non-dispatchable resources and retire dispatchable resources, more transmission system infrastructure will be needed in the upper Midwest”

“Additional transmission infrastructure will:

  • “Mitigate some of the negative impacts that retirement of dispatchable resources has on system stability and reliability;
  • Increase the options available for siting dispatchable and non-dispatchable resources in locations that are optimal for energy production;
  • Capture weather driven diversity from remotely-sited, non-dispatchable resources.”

This is interesting because spending a lot of money on new transmission lines will mitigate some of the negative impacts that will occur if we retire our dispatchable resources, but not all of them. This means that there will likely be even more costs associated with adding more wind and solar to the grid.

Also, capturing weather driven diversity from remotely-sited, non-dispatchable resources” sounds an awful lot like building more transmission just to incorporate more renewables. If new transmission lines are needed for this reason, these costs should be paid for by renewable developers, and not socialized on the backs of ratepayers.

Finding Four

“Non-dispatchable resources alone will be incapable of meeting all consumer energy requirements at all times. Dispatchable resources and/or energy storage with capacity for multi-day support will be needed.”

  • The increase of non-dispatchable resources combined with the retirement of dispatchable resources will put pressure on maintaining a sufficient supply of energy to match consumer demand at all times.
  • Abrupt changes in weather, including prolonged extreme weather conditions, sudden changes in consumer demand, or disturbances on the transmission system (i.e., outages) will increasingly challenge the ability of the electric grid to provide a continuous supply of energy as more non-dispatchable resources are added.
  • Adding more non-dispatchable resources alone will not mitigate insufficient energy supply. For example, under certain extreme weather conditions non-dispatchable resources would produce little additional energy when needed. At other times, these non-dispatchable resources would provide more energy than required to meet consumer needs and must be curtailed or exported.
  •  As non-dispatchable resources are added, sufficient dispatchable resources, which may include significant amounts of energy storage will be needed to maintain a reliable transmission system.
  • Dispatchable resources and/or storage will be needed for periods when nondispatchable resources are not sufficient to meet consumer demand. To be an effective dispatchable resource, storage would need enough capacity to provide energy for multiple consecutive days and/or during unusual weather conditions when there is not enough excess energy from non-dispatchable resources to re-charge the storage devices during that period.

This last section of the report is interesting, because it pretty much lays out, in no uncertain terms, that the grid will be harder to maintain and potentially become less reliable in a future where wind and solar are asked to do the heavy lifting now done by coal, natural gas, and nuclear power plants.

The admission that dispatchable, or “real” power plants will still be needed underscores the points Center of the American Experiment has been making for years, renewables cannot actually replace coal, nuclear, or natural gas because they simply cannot be counted on to show up to work. That means we will still need natural gas power plants for “backup” when the wind doesn’t blow or the sun doesn’t shine.

This is why any attempt to pave the way for more wind and solar will ultimately increase the cost of electricity. CapX2050 essentially says we’d need to build a lot of expensive transmission lines to have more expensive, less reliable electricity than we currently have.

This should be a giant signal not to keep pushing wind and solar.

How much will it cost?

The one thing Capx2050 did not detail was cost, but we have good reason to think  Capx2050 will be much more expensive than Capx2020. Capx 2020 spent around $2 billion on 800 miles of transmission lines, which equates to a cost of about $2.5 million per mile.

Costs for the next round of transmission lines could range from $1.6 million to $4.4 million per mile, depending on the voltage of the line, according to the regional grid operator, the Midcontinent Independent Systems Operator (MISO). Capx2050 did not give out an estimate for how much transmission would be needed, but some preliminary estimates for the cost that I have heard put the cost of new transmission at around $12 billion.

Spending billions of dollars on transmission lines to connect wind and solar facilities that will deliver inferior service to the service we currently enjoy is not a wise policy.