Energy Use and Greenhouse Gas Production

Energy Use
In a dry year, the proposed desalination plant would provide 13% of Santa Cruz’s normal year water delivery, while doubling the Water Department’s electricity consumption.1  In a normal year, Soquel Creek Water District would use the plant at 1 million gallons/day. The District would be able to cut back 23% on pumping water from the aquifer. But the District’s electricity consumption would more than double, not including the power to convey the water from Santa Cruz.2
The Environmental Impact Report (EIR) for the Integrated Water Plan, the policy that commits the City to move forward towards desalination, considers increased fossil fuel dependency to be an insignificant impact:
Impact 5.13-3: The proposed Program would increase reliance on energy resources that  are not renewable. Less than Significant.
We vigorously disagree. Increasing reliance on fossil fuels has a profound impact on our community’s economic and social well-being. The opening article in this document makes the case that our community needs to become more resilient in the face of declining fossil fuel energy supplies. It doesn’t make sense to commit to a new water source that requires 8 times the power to pump water out of the ground and many more times the power requirements of surface water, which is delivered mainly by gravity.
The EIR justifies the use of fossil fuel by claiming public health depends on it:
“However, because this use of natural  resources would be used to meet the objectives of the proposed Program, primarily to provide a  reliable water supply and ensure protection of public health and safety, commitment of these  resources would be justified.”3
Is public health really at stake? I consider that question on page 4.

Sea level rise @ Santa Cruz

Area in Santa Cruz below sea level, with a 1 meter rise (predicted by 2100)

Greenhouse Gas Emissions
With half of its source  power coming from fossil fuel burning plants, the desalination plant will increase greenhouse gas emissions. The impact of sea level rise on this coastal community is so vast as to be difficult to comprehend. Yet the EIR for the Integrated Water Plan did not include one mention of “greenhouse gas emissions” or “climate change” in its 627 pages.
The state’s AB 32 requires a 30% reduction in greenhouse gases by 2020 and 80% by 2050. How in the world will the City, and especially Soquel Creek Water District (which plans to use the plant in 51/2 years out of six) comply with AB 32?
The energy consultant for the project has advised the water agencies that they don’t have to comply with AB 32. “AB 32 does not directly apply to the project, and it does not provide a mandate for SCWD2 to reduce Scope 2 emissions.”4  Scope 2 emissions are those don’t occur on site, but occur as a result of the power use. The consultant’s interpretation of AB 32 is dubious. Moreover, our assessment is that this community would not favor an evasion of AB 32 on such a technicality. The consultant’s principal strategy recommendation for “offsetting” greenhouse gases is the purchase of Renewable Energy Credits. Our article, “Turn On the Greenwash Wipers” investigates these credits.

1 Total 2005 electric power use of SC Water Dept = 6,414,031 kw-h.  (Source: 2005 Santa Cruz Greenhouse Gas Emissions Inventory, Table 1) At 75gal/kw-h the plant running 6 months at 2.5 million gal/day would require 6,066,666 kw-h
2 Energy calculation:
“The total energy consumed by the District last year was approximately 3,500,000 kwh.  Approximately 85-90% is used for production (wells, treatment, etc.) and 10-15% is used for conveyance (to move/pump the water throughout the system)”.
Soquel use at 1million gal/day = 365 million gal/yr
At 13kwh/1000 gal, 365 million gallons uses 4,745,000 kwh

District cut back in well production:  4800AF  (1,564 million gallons)
Less 365 million gallons from desal  (23%) = 1,199 mil gal net pumping
With 23% less pumping of groundwater, electric consumption due to pumping drops by = 23% x 85% x 3,500mw-h = 684 mwh
Net consumption = 3500 – 684 = 2,816mw-h
New electric use = Desal electric +  Net Groundwater pumping use  (not counting conveyance from Santa Cruz)
4,745mw-h + 2816 = 7562mw-h or 216/% of current use —Not counting additional needed power for conveyance from Santa Cruz
3 Draft Integrated Water Plan Program EIR (2005) p 1-26
4  CH2M Hill progress report on their Energy Minimization and Gas Reduction  Plan, 10/09

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