Comments on proposed pumped storage project in Marmora, Ontario

What follows are my submissions to the IAAC on the filings presented by the proponents of the Marmora pumped storage project and authored by the engineering firm Hatch. 

Prioritise Public Safety

The proponents indicate their intention to build a large water reservoir immediately above a community where significant numbers of people live in permanent residences – what has been described as “a lake in the sky”.

At p.  24 (of the print version), the Hatch summary report acknowledges that community members have raised concerns about the design and safety of the upper reservoir.

Those concerns should be central concerns of IAAC.

The failure of a pump storage upper reservoir at Taum Sauk in Missouri in 2005 illustrates the destructive potential of an elevated artificial reservoir. The size of the failed reservoir at Taum Sauk was approximately the same as that proposed over top of the town of Marmora. Only the very fortunate timing of the Missouri failure prevented what could have been a major loss of life.

One might expect the proponent’s engineer to pay particular attention to safety concerns. On the contrary, the thinness of the Hatch report on safety seems remarkable. All the report provides is the following comment:

The Upper Reservoir is proposed to be constructed on the northeast portion of the existing non-reclaimed broken rock pile to function as a headrace pond. Construction of an upper containment dam with an impervious liner will be required, with the on-site materials being utilized to the extent possible. (Section 2.4.1.2)

One might hope that the safety challenges inherent to storing a very large volume of water in an artificial bermed lake high above a vulnerable downstream population would merit greater attention.

I urge the IAAC to prioritise public safety in its deliberations, especially with respect to the potential failure of the upper reservoir.

Using roller compacted concrete instead of mine ruble for berming the headrace would appear to be an appropriate consideration. Spillway design should also receive careful consideration. Instrumentation and controls are also an avenue that needs development. None of these considerations are addressed in the Hatch report.

Misleading Project Description

The project description is fundamentally misleading. Here's an example:

"Waterpower projects are designed for long life spans, typically in excess of 100 years with ongoing maintenance, repair and upgrade programs. As such, decommissioning of the facility is highly unlikely to happen in less than 100 years. Once the facility has reached the end of its service life, additional redevelopment, rather than decommissioning, would be an option that should be considered again to further extend the life of the facility." (P. 8)

Except for the 30 MW solar power component, which is merely a decorative appendage of the proposal newly inserted into the project’s scope, the proposed pumped storage project is not water powered but grid powered. While the business case for the proponents of the project are a function of whatever contract the government of the day happens to commit the public purse to, the fundamental economic proposition for consumers underpinning any grid storage project is in principle very simple. 

The value proposition for energy storage is a function of the ability of the project to recover its costs by buying electricity when it is inexpensive and reselling a portion of that original electricity less the parasitic losses back to the grid when the price is higher. 

Once constructed, the ongoing incremental or operating costs of the facility will ultimately limit the economic life of the facility. Those operating costs will include amounts for maintenance and very small amounts for staffing but will also include the facility’s parasitic energy losses. As governed by the Second Law of Thermodynamics, energy storage projects are net energy consumers, not net energy producers. 

The economics of grid-powered pump/generation storage are completely different from those of a waterpower project. Waterpower projects are net energy producers, not net energy consumers, and therefore decommissioning considerations and the value of continued operations for hydropower projects are of limited usefulness in consideration of pumped storage projects. The similarity of equipment for pump/generation storage vs. water power should not obscure this basic difference.

The economic viability of baseload or run-of-river waterpower generators are not affected significantly by the variance between peak vs. off-peak electricity prices. However, for energy storage projects, that price differential is fundamental to their potential to earn revenue. If market conditions cause prices to vary less, energy storage becomes useless. Predicting price variability trends over the long term is speculative at best.

Parasitic energy losses will be due primarily to groundwater seepage into the pit, precipitation, and electrical/mechanical losses. The longer Hatch report assumes that the surplus water accumulation rate will be 864,000 L/day but this rate is currently subject to investigation.

The Hatch report states:

"A detailed geotechnical groundwater modelling exercise is underway to accurately assess any potential groundwater recharge/discharge effects, effects to nearby aquifers and to a lesser extent groundwater quality." (P. 12)

A historical plaque once associated with the Marmora mine site reported that during operations, “TWO 250 HP PUMPS REMOVE 20,000,000 GAL. OF WATER FROM PIT EVERY MONTH”, a cost factor that no doubt contributed to the mine’s closure. This dewatering rate is approximately 3.5 times the rate assumed by Hatch.

The rate of water ingress into the pit is a function of how empty the pit is. This basic relationship is illustrated by the water level data provided by Hatch at p. 48 of the “Initial Project Description” report. Over the first eight years after mining operations stopped, the average annual rise in the pit water level was approximately 7.6 times the rate of rise in recent years. (Albeit, the somewhat conical shape of the mine pit would have had some influence on the rate of rise of the water level.)

The only time the Marmora facility will have the potential to earn market revenue is when the pit is empty. This suggests that the normal state of the facility is likely to be with the pit empty. This empty state will maximise the potential for water ingress.

The overall prospects for this facility to generate value from a consumer perspective is highly suspect. Note that Ontario already has a pumped storage facility at the Beck complex at Niagara. Relying on data from the IESO's Generator Output and Capability Report as summarised by energy analyst Scott Luft, the average annual utilisation of that facility was roughly 8.1 times higher during the period 2008-2015 as compared with the period 2016-2022.

If value to consumers is a test that the Marmora facility is ever put to in future, it appears unlikely that the proponent’s claimed 100 year lifetime for the facility will be realised. 

Pumped Storage as an Amusement Park

The first two sentences of the Hatch report clearly intend to highlight a feature they want foremost in the mind of IAAC:

"Northland Power Inc. (NPI) and Ontario Power Generation (OPG) are proposing a $2.0 billion investment for electricity system infrastructure that has the potential to provide a major electricity system asset and economic development engine for eastern Ontario. As one of Canada’s first closed-loop pumped (hydroelectric) storage facilities, the “Marmora Clean Energy Hub Project” (“Clean Energy Hub” or “the Project”) is projected to generate an economic impact of up to $32 million per year in the Municipality of Marmora and Lake, in Hastings County, Ontario."

The reference supporting this apparently exciting $32 million per year of economic impact is a report with the hyperventilating title “Recharge Marmora” authored by A-Frame Content & Marketing in 2014 and funded by the Ontario Ministry of Tourism, Culture and Sport. The actual revenue generators that A-Frame imagines include a multi-use trail, a zip line and a campground.

I suggest that the IAAC should give little weight to questions of whether or not an industrial energy storage facility can become a tourist attraction.

All of this is submitted for your consideration.

Tom Adams