A brief comment re DC. The big cost is the AC to DC and DC to AC converters at each end, which tends to make DC a point to point system without interconnections along the way. In practice this has limited DC to long distance transmission, typically from remote generators (hydro power in northern Manitoba is an example). DC has also been used for under ocean lines (e.g. a connection between the north and south New Zealand islands) and for interchange between disconnected grids (between western and eastern North America).
Peter Peter Flynn, P. Eng., Ph. D. Emeritus Professor and Poole Chair in Management for Engineers Department of Mechanical Engineering University of Alberta [email protected] cell: 928 451 4455 *From:* [email protected] [mailto: [email protected]] *On Behalf Of *Michael MacCracken *Sent:* Sunday, September 17, 2017 9:15 AM *To:* [email protected]; [email protected] *Cc:* geoengineering <[email protected]> *Subject:* Re: [geo] Swanson's law A problem at present is that present high-voltage/alternating current distribution lines mean that low-cost transmission of electricity is limited to a few hundred miles, so one would have to disperse DAC. If instead there were large-scale high-voltage/direct current distribution lines (see MacDonald et al., Nature, January 2016), then there could be long distance, low-cost transmission over large distances and one would have a much better likelihood of having access to any stranded energy (from wind, solar, geothermal, nuclear, etc.), all while having DAC located where it would be optimally able to store the captured carbon. Just another reason, among many, for having large-scale HV/DC networks across the world's continents. Mike MacCracken On 9/17/17 10:50 AM, Hawkins, Dave wrote: Using stranded renewable energy for DAC is an interesting idea. Question is what energy resource will be used during periods when there is no surplus RE? If DAC does not run 24/7 its costs go up. If DAC uses RE to run 24/7, that requires a larger RE system with associated stranding. If DAC uses something other than RE, what is it? Ideally, we would have an economically dispatchable zero-carbon resource. This is not an argument against DAC, just an observation on system complexity. Sent from my iPad On Sep 17, 2017, at 3:58 AM, Andrew Lockley <[email protected]> wrote: Does anyone have a breakdown of projected input costs for Direct Air Capture? I'm interested in quantifying the energy component. Swanson's law predicts reliable falls in the cost of solar. Without storage, much peak-time solar could be wasted, unless it's used for time-insensitive applications like DAC or desalination. (I understand Keith's process needs electricity, but Lackner's instead needs heat.) My hypothesis is that DAC could become vastly cheaper, if energy costs trended down as expected due to Swanson's law, and cheaper still if it became a way to use this stranded energy. I'd welcome thoughts, data, projections and comments. Thanks Andrew Lockley -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout.
