Editor’s note: This commentary is by Willem Post, a retired engineer, who now writes about energy issues, currently specializing in energy efficiency of buildings and building systems. He is a founding member of the Coalition for Energy Solutions.
[R]enewable energy proponents are using a new catchy mantra “Energy Independent Vermont” to justify imposing a regressive carbon tax. Some legislators repeat it as part of their campaign rhetoric and renewable energy talking points. Either they do not know what that implies or are engaged in another scam of the gullible.
Vermont imposing a unilateral carbon tax of $500 million per year by 2027 would be economic suicide, as it would transfer up to $500 million per year, less sales tax reduction, into incompetent, ponderous, inefficient government hands (EB-5, health care website and the Montpelier district heating plant come to mind), for distribution by that government to pressure-group-determined “worthy” programs.
For example, owners of rental properties would be clamoring for maximal subsidies to upgrade the energy efficiency of their energy-hog buildings, something they would have done years ago, if an enforced state energy code for buildings would have required it.
Below is a description, with numbers, of two alternatives:
Alternative No. 1, Vermont Energy Independent
For Vermont to be truly energy independent, it would have to disconnect from the New England electric grid (not use it as a crutch), and produce ALL of its energy — not just electrical energy — from home-grown energy sources, plus have enough energy storage capacity, in various forms (not just electrical), to ensure adequate energy supply to the Vermont economy 24/7/365, year after year. The capital cost and environmental damage of the wind, solar and other energy systems, plus grid system expansion, plus energy storage systems would be very high.
Existing wind and solar: At the end of 2015, Vermont’s homegrown wind and solar were:
Homegrown energy supply: The present supply to utilities is about 6,200,000 megawatt hours (MWh) per year. Green Mountain Power’s Integrated Resource Plan projects it to be about 9,066,000 MWh in 2050, a 46.2 percent increase, due to increased use of heat pumps and electric vehicles, and decreased use due to energy efficiency. That, from mostly homegrown wind and solar sources, would supply about 65 percent of Vermont’s total energy in 2050.
The supply and storage of the other 35 percent, or 4,881,692 MWh, mostly as homegrown thermal energy, is much more difficult without using fossil fuels, and has yet to be determined. For example, if biomass, i.e., wood chips, the sustainably harvested land area would be 3,332,243 acres (4,881,692 MWh / {(10 million Btu/acre / 3,413,000 Btu/MWh) x overall efficiency 0.5}) in addition to the areas used by the generating plants in Burlington and Ryegate, etc., clearly an impossibility.
Wind and solar systems have useful service lives of about 25 years, and would require periodic major capital investments to maintain a reliable energy supply.
Alternative No. 2, Vermont Partially Energy Independent
A much better approach would be for Vermont to be partially energy independent, i.e., connected to the New England grid, with an assumed electrical energy mix of 25 percent in-state wind, 25 percent in-state solar, 40 percent hydro from Hydro-Quebec, and 10 percent other (the existing McNeil and Ryegate wood-chip-fired power plants, small hydro plants, small bio plants, etc., plus any new power plants. The efficiency of wood-chip-fired power plants is about 25 percent). Hydro-Quebec has massive energy storage systems to smooth the daily and seasonal wind and solar energy variations to ensure a continuous, steady, low-cost, near-CO2-free, electricity supply 24/7/365, year after year.
NOTE: Solar energy is variable and intermittent, because it varies from minute to minute, due to variable cloud cover; is minimal during winter, maximal during summer; and is minimal or zero about 75 percent of the hours of the year. Wind energy is variable and intermittent, like the wind, is least during summer; and is minimal or zero about 40 percent of the hours of the year. Many hours of the year, the sum of wind and solar energy is minimal or zero, per ISO-New England’s grid status website, i.e., unlike coal, nuclear, gas, hydro, bio and geo, wind and solar, without viable utility-scale energy storage systems, are not reliable energy sources.
Below is an analysis of the above electrical energy mix.
Wind 25 percent: Wind turbine system capacity required = (9,066,000/4 MWh/y)/(8760 h/y x 0.33, average capacity factor) = 784 MW
Lowell has 21 turbines, or 63 MW on 3.5 miles of ridgelines, plus about 3 miles of access roads to get to the ridgeline. The capital cost was about $150 million, plus about $20 million to connect it to the grid.
Lowell-type systems required = 784/63 = 12.4
Ridgeline miles required = 12.4 x 3.5 = 44
Capital cost of Lowell systems = 12.4 x $170 million = $2.116 billion
Solar 25 percent: PV system capacity required = (9,066,000/4)/(8760 x 0.15 average CF) = 1725 MW
PV system enclosed by a fence = 7 acre/MW.
Equivalent to about (800) 2 MW PV systems spread throughout Vermont.
Fenced in meadow area required = 1725 x 7 = 12,074 acre, or 19 square mile.
Capital cost = 1725 MW x 3.5 million/MW = $6.037 billion
Hydro 40 percent: Two 1500 MW transmission lines would be required, each capable of providing all of Vermont’s peak demand of about 1400 MW in 2050, in case the sum of wind and solar energy is zero. In case of both lines failing, the connection to the New England grid would take over, i.e., Vermont likely would rarely, if ever, be without power.
The cost of the near-CO2-free hydro energy to utilities would be about 6-7 cents per kWh, adjusted for NE wholesale prices, plus about 1 cents per kWh for transmission.
Capital cost about $3.5 billion
Total capital cost = 2.116+ 6.037 + 3.500 = $8.156 billion, plus about $1.5 billion for grid build-outs = $9.656 billion.
The capital cost of homegrown energy systems for the other 35 percent of Vermont’s total energy needs likely would be about $5-$6 billion.
NOTE: The capital cost of such an energy system would still be enormous, even if energy efficiency were such that total energy consumption in 2050 would be 50 percent of consumption in 2016.
NOTE: Wind and solar systems have useful service lives of about 25 years, and would require periodic major capital investments to maintain a reliable energy supply. Almost all existing systems would need to be at least partially replaced before 2050.
Additional capital costs: In addition to above capital costs, there would be the multi-billion dollar capital cost for:
• Heat pump-based heating and cooling systems to replace existing systems for almost all buildings.
• Electric vehicles and chargers to replace almost all existing light duty vehicles, i.e., cars, SUVs, minivans, ¼-ton pickups.
• Significantly upgrading the energy efficiency of almost all buildings.
• Significantly upgrading the overall energy efficiency of almost all businesses.
The levelized cost of energy, cents/kWh, produced by such a system would be at least 2-3 times of the existing system, on a real-cost basis.
