US Coal Transitions

Developing EPA carbon regulations could shutdown most U.S. Coal Power possibly within 25 years.  A previous Part 2 Post describes how 80% of Coal Power could be feasibly replaced by expanding Wind+Solar Power up to a 30% penetration level by 2040.  This would require installing 700% greater new Wind+Solar Power capacity than currently exists and almost a 50% increase in Nuclear Power capacity 2013-2040.  Replacing most Coal Power with variable Wind+Solar will require maintaining adequate reserve or backup power capacity needed to reliably operate all Power Grids.  Total new Power capacity capital costs are estimated at $2.9 Trillion, which could effectively double future Consumer power costs compared to EIA AEO 2013 projections.  

Replacing 80% of Coal Power with Wind+Solar and Nuclear Power should reduce U.S. carbon emissions by 1.6 Billion metric tons per year or by 28% of total projected U.S. carbon emissions in 2040.   Achieving this carbon reduction will not only require a huge expansion of zero carbon power generation technologies, but will also require significant trade-offs.  Required trade-offs to facilitate rapidly shutting down most Coal Power will include significant impacts on many local and regional environments, and possibly major changes to current new facility permitting processes.  This Part 3 Post will cover these more significant impacts of shutting down most U.S. Coal Power by 2040.

Brief Review of the AEA 40% RE in 2040 –The Part 2 Post summarized a cost effective solution to reducing 80% of Coal Power generation compared to the AEO 2013 (Reference case) projection; 2015-2040.  This ‘Alternative Energy Analysis’ (AEA) was designed to reduce Coal Power by primarily expanding Renewable Wind+Solar Power.  Increasing Wind+Solar Power up to a 30% net generation penetration level, in addition to the AEO 2013 original projections to increase all other Renewable Power sources (biomass, geothermal, bio-waste and hydropower) by 10%, would increase total  ‘Renewable Electricity’ (RE) up to 40% by 2040.  Since Wind+Solar growth was limited to a relatively aggressive level of 8% per year, the balance of required power generation created by shutting down Coal Power (and not met by expanded Wind+Solar) was supplied by new expanded Nuclear Power Generation.  The AEO 2013 power capacity and generation mix is compared to the AEA 40% RE case study in the following data table.

Table 1 – AEO 2013 and AEA 40% RE in 2040Image

Data Source: EIA AEO 2013 and Impacts of Shutting Down Most Coal Power-Part 2 final analysis.  

To reduce current Coal Power net generation by 80% from current (2013) levels requires increasing Wind+Solar and Nuclear Power capacities by 386 GW and 38 GW respectively above the EIA AEO 2013 projections.  Note that all other Power capacities and net generation(s) are held constant between the AEO 2013 and AEA 40% RE in 2040 case study.

Projected Electric Power Reserves – One of the most critical components for feasibly developing a proper power generation mix necessary for ensuring future Power Grids’ reliabilities is providing adequate ‘reserve’ or backup power.  Required levels of ‘net’ reserve power vary by region and season of the year.  This factor is most often discounted or ignored in many studies or theoretical proposals that advocate substantially greater Wind+Solar Power above the 30% penetration level developed in the AEA 40% RE case study.  To illustrate, refer to the following data table.

Table 2 – AEO 2013 for 2015&2040, and NREL 80% & AEA 40% RE in 2040Image

Data Source: EIA AEO 2013 and Impacts of Shutting Down Most Coal Power-Part 2 final analysis.  Note: all TWh data are based on ‘net generation’.  ‘Gross Reserve’ power capacity (%) is based on EIA average capacity factors   

The AEO 2013 projects that ‘gross’ power reserves will decrease from 71% to 50% 2015-2040.  Note: ‘gross’ power reserves are typically at least twice the level of actual ‘net’ power reserves on-line/available to stabilize and ensure Power Grids’ reliabilities.  Off-line power capacity is due to routine shutdowns required for maintenance and upgrades/renovations.  This AEO 2013 projected reduction in estimated gross reserve power assumes a large amount of current excess reserve capacity is either switched to baseload service or is shutdown by 2040.  

Both the NREL 80% RE and AEA 40% RE assume that new Wind+Solar capacity will be located in more cost effective and optimal locations around the U.S. to maximize capacity factors, and are connected into existing Power Grids at the most efficient system integration locations.  The AEA 40% RE case study assumes a significantly more conservative level of reserve/backup power capacity needed for reliably increasing variable Wind+Solar Power than the NREL 80% RE report. 

Maximizing Wind and Solar Power Capacity Factors – To maximize Wind and Solar capacity factors and minimize ‘net generation’ capital costs requires locating these variable power sources in the most ideal locations around the country.  In the case of wind this generally means locating the new Wind Farms along the Coasts and Great Lakes, and within the Mid-continent.  Refer to the following map.

Map 1 – Optimal U.S. Wind Farm LocationsImage

Data Source: NREL ‘Renewable Electricity Futures Study Executive Summary’, Figure ES-2.    

Coastal Wind Power capacity factors approach 40-50% levels compared to the ideal Mid-continent locations that average 30-35% maximum.  The less ideal locations (Mid-west/east) will have Wind capacity factors at significantly lower (5-10% +/- absolute) levels. Many major cities or populations centers with high electric power demands are fortunately located in many of the Coastal areas more ideally suited for new/most efficient Wind Power capacity.  The Mid-continent is somewhat less ideal due to lower wind intensities and generally lower population/consumer densities in this part of the country.

Similar to Wind Power, new Solar Power can and should be built in the more ideal locations around the country.  Refer to the following map.

Map 2 – Optimal U.S. Solar Power Facitlities LocationsImage

Data Source: NREL ‘Renewable Electricity Futures Study Executive Summary’, Figure ES-2. 

The most optimal locations for Solar Power are in the Southwest and generally the Southern U.S.  This factor does create some synergies with Wind Power, particularly in the Northern and Northeast regions of the U.S.   Northeast Solar Power average capacity factors are about 10% vs. average maximum Solar capacity factors up to 25% in the Southwest regions.  Northeast Coastal regions are more ideally suited for Wind Power with capacity factors >35%.

To maximize both Wind and Solar Power capacity factors and minimize capital costs will require locating and building large Wind Farms and (centralized) Solar Power facilities in the most ideal locations around the country.  This will require numerous trade-offs in properly locating new Wind/Solar in areas that could be strongly opposed by the NIMBY crowd and many other special interest groups.  Optimal new Wind/Solar Power will also require construction of many thousands of miles of new high voltage ‘power transmission’ lines in order to optimize the connections into existing Power Grids.  This is required to efficiently manage Power Grid supply-demand balances and the associated ‘power distribution’ systems.  Besides optimizing variable Wind/Solar Power Grid installations locations and connection points, the level and availability of required reserve power plants is another design requirement to maximizing systems’ efficiencies and minimizing transportation & distribution (T&D) lines/system power losses.

Impacts of Smart Grids and Demand Response – Some of the primary reasons why the NREL 80% RE report assumed that power reserves could be substantially reduced (35% vs. AEO 2013 50%) is due to the assumption that advancements in ‘Smart Grids’ and customer ‘Demand Response’ could feasibly enable  cutting the level of required backup power for expanded variable Wind+Solar Power generation.  While this assumption is directionally feasible, the NREL level of reducing required gross power reserves is highly questionable and could put Power Grid reliabilities at significant risk.

All Power Grids are designed to balance and manage/control power generation/supply with demand.  Basic power system controls were designed to protect generation equipment (from mechanical failure) ‘first’ and supply consumer (uninterruptable) demand ‘second’.  Overtime Power Grids’ control technologies and reliabilities have improved substantially.  Today, the number of major power failures is relatively small, and most often due to weather related mechanical failures of T&D power line/infrastructures.   In recent years Power Grid management-controls advancements/upgrades are often referred to as ‘Smart Grids’.  As the level of variable, non-dispatchable Wind+Solar power increases, the current Smart Grid advanced controls must be further and significantly upgraded to maintain the current level of Power Grid operating reliabilities.

Centralize Smart Grids have been further upgraded to include individual customer ‘Smart meters’.  Smart meters were initially designed to reduce operating costs and enable Power Companies to bill Customers actual/real-time prices vs. actual purchased/generated power costs; instead of the past estimated average costs only.  The new Smart meter technology also became the basis for facilitating Customer ‘Demand Response’.  Smart meters provide individual Consumers with real-time cost data so that they can more economically manage their power consumption.  The problem with this Demand Response strategy is that current Customers’ active participation is almost totally voluntary and relatively small.  The vast majorities of U.S. Power Grid customers have grown accustom to uninterruptable or on-demand power and may or may not significantly reduce their future power consumption during peak power-demand periods.  How significant the impact of possibly doubling future power costs on total consumption is to-be-determined.

Environmental and Permitting Trade-offs for Rapidly Expanding Wind+Solar Power – To expand Wind+Solar Power up to a 30% (net generation) penetration level, and do so cost effectively, will require rapidly installing new generation facilities in the most optimal locations around the country.  In the case of expanded Wind Power, a large percentage of the new generation capacity needs to be installed along most coastal regions and off shore.  To truly achieve the Wind+Solar 30% penetration target by 2040 will require installing 325 GW and 110 GW of new Wind & Solar respectively (2015-2040).  Based on average energy densities (Wind= 2.5 watt/meter2 & Solar= 10.0 watt/meter2) the total land required for these renewable power developments will be about 54,000 sq. miles (area greater than the state of Arkansas).  This estimate excludes the required new T&D and associated infrastructures.

Another required trade-off or consequence of rapidly expanding U.S. Wind Power over the next 25 years is largely ignoring the risks to the native bird and bat populations in proximity to the new Wind Farms. 

To install 435 GW of new Wind+Solar Power over the next 25 years will require substantially speeding up the current permitting processes.  The 10 year permitting period required for the planned Cape Wind Nantucket Sound project must be reduced to a maximum of 1-2 years for all future on-shore Wind/Solar or off-shore Wind Power projects.  The NIMBY crowd and many Environmental groups will find such a change unacceptable, but longer term delays will make the Wind+Solar Power 30% penetration level expansion by 2040 highly infeasible.  The same expediting of the construction-operating permitting process needs to apply equally to all new T&D projects routings required to optimally integrate new Wind and Solar Power capacity into existing Power Grids.

Needed Government Planning and Policies to Optimize Expanding Future Renewable Power – To actually expand total U.S. Wind+Solar Power from the current 5% penetration level up to 30% in 2040 will likely require a Government policy better designed than developing random EPA emission reduction regulations, current miscellaneous State renewable portfolio standards, or possible future new carbon taxes.  A more sound regulatory strategy would be to develop a reasonably feasible and more comprehensive plan for how best to retire existing Coal and eventually Natural Gas Power, or a U.S. wide future Electric Power Renewable Standard.  Organizations such as the NREL have many of the needed resources to help develop a more reasonable and comprehensive future Power Mix Regulatory plan, but the leadership should probably come from a more qualified organization such as the NERC.  In addition the FERC and major Power Companies should participate in the future Power Standard plan’s development.  Such a new Power Standard development team should be able to establish a much more cost effective and feasible plan to reliably transition the U.S. to a lower carbon power generation future.  Once developed and properly peer reviewed, the future renewable power mix plan should then serve as the basis for a much more feasible and achievable Federal Renewable Power Standard.  Such a Regulatory strategy should also be approved by Congress.

Options to the AEA 40% RE Case Study – There are a number of very feasible alternatives to just rapidly expanding Wind+Solar Power and needing to compromise on the many environmental impacts.  One of the more promising zero carbon technologies is Advanced Nuclear Power.  Nuclear can cost effectively displace all Coal Power and a large amount of Natural Gas Power without the need for large levels of the reserve/backup power required by increasing variable Wind+Solar Power.  Increased Nuclear Power will have a substantially smaller physical footprint than variable Wind+Solar, and can be installed at existing Coal Power plant locations, which should minimize the need for thousands of miles of new high voltage transmission lines.  This not only substantially reduces the amount of natural lands that must be cleared for new Wind/Solar facilities and associated infrastructures, but also eliminates the risks to airborne wildlife.  These Nuclear Power advantages vs. Wind/Solar could also minimize the new power plant impact concerns of the NIMBY crowd and eliminate many other environmental concerns such as the negative impacts on existing natural and pristine coastal/off-shore regions.