Editor,
I’m not going to wade into the calculations he used but they should be verified (referring to Stephen Carr’s letter to the editor The Inconvenient Cost Of Pumped Storage Over Battery, published September 17).
I do have other observations about his assumptions that makes me doubt his idea.
– He did not describe what battery technology he would use. There are a few I can think of but they are relatively new, not widely deployed nor proven for 50-100 year lifetimes. Surely he would not recommend lithium battery technology. I have experience with Tesla batteries in my car and home. It’s good that Tesla has a 10-year warranty on them as they failed and had to be replaced at 6 and 5 years.
– Battery capacity and charging efficiency varies with temperature and age. Over time battery efficiency declines. He did not factor that reality into his estimates. OPS unaffected.
– Batteries are at risk from forest fire, tornadoes and flood. OPS is not. It’s all underground.
– There is no proven commercially available battery that will last 50-100 years. Perhaps the cost he assumes ($5B) covers 5 replacements of 10 year battery lifetimes. We don’t know, he did not disclose how he arrived at this cost.
– To my knowledge the final design of OPS is not done. The cost ($10B) is his estimate. We don’t know, he did not disclose how he arrived at this cost.
– 14 cents/kw seems high; especially if the charging is done in off peak hours at lower rates. This has a big impact on the cost difference he presents.
– Distributing the battery displacement across several sites under existing high tension wires may not be practical as it increases the cost of installation. This idea would increase the cost and maintenance of connecting the batteries into the grid. Again, the details are not defined.
– Carr did not address the benefits that accrue to Meaford from implementing the OPS solution. ($1M/year is a number I have read). Presumably there are no side benefits that accrue from implementing a battery solution or surely he would have mentioned them.
– Carr has not identified any company that will design and install a battery solution for $5B.
I for one would not trust his estimates just because he is a retired engineer unless he provides a detailed, costed-out plan we can verify.
I will trust the many experts behind the detailed OPS plan vs one retired engineer’s ideas.
David MacDougall, Meaford
