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Trading fish for carbon emissions

The NY Times has an interesting article today on the debate in the Pacific Northwest over removing hydroelectric dams to restore wild salmon populations. The article talks about how Indians and commercial fishermen have been hurt by the decimated salmon populations, and how farmers could stand to lose if the dams are removedBonneville Dam My personal position is this should be carefully evaluated on a case by case basis. If the dam is fairly small, then it may be worth removing. If the dam is relatively large, then firm plans must be developed to replace it with other renewable sources. Simply saying replace it with solar or wind is not sufficient since those are intermittent sources. If dams are haphazardly removed, it is likely they will be replaced with more coal or natural gas plants.

Dam Minneapolis

The Star Tribune covered prospects of adding a new hydroelectric dam to St. Anthony Falls in Minneapolis. There is some concern that it will damage the mill ruins. I was curious about a few oddities with this proposed project.

It will apparently generate enough electricity to power 2000 homes, but will only run at off peak hours.

Crown Hydro spokesman Rob Brown said water would drop through thick, durable steel pipes and wouldn't harm the mill ruins. The company would negotiate the amount of water it would leave flowing over the falls and regulate it with a computerized device, he added. Crown Hydro would run mostly at night and other non-tourist hours, Brown said. And he assured people there wouldn't be vibrations.

Evidently, the existing Xcel dam has significant periods of lessened generation due to low river levels.

Xcel's plant, which has five turbines, ran at partial capacity 22 percent of the time from the most recent time frame available, 1992 to 1997, because of low river flows, officials at Xcel said.

The idea of putting in a new facility that may negatively impact the ruins to supply a little bit of non-peak energy, assuming river levels are consistently high enough for both dams, seems suspect. That being said, I suppose it will tend to offset coal baseload so there is an upside.

RES Thursday

The Senate Energy Committee is preparing to debate whether it will beef up the Renewable Energy Objective (requiring utilities to make good faith efforts toward providing x% of their power from renewable technologies) or a Renewable Energy Standard (mandating utilities provide x% of power from renewable energies).

These bills will be discussed in Room 123 of the Capitol at 3:00 on Thursday, 18 Jan, 2007.

According to the Senate Energy Committee schedule they will discuss S.F. 4 and S.F. 74 as well as S.F. 145 and S.F. 129. I have not had a chance to review the 2 latter bills, they appear to be more all-encompassing bills that will establish either a standard or objective while dealing with many other issues as well.

Currently, there are 3 RES/REO-only bills under consideration although 2 of them appear identical to me. I stared at S.F. 4 and S.F. 113 for a good 10 minutes and could not detect any difference between them. Both bills create a RES. The 3rd bill is S.F. 74 and that would beef up the REO.

The Senate bills each change the requirements on small hydro. Previously, hydroelectric generation had to be below 60MW in order to count toward the REO. The new REO or RES would change that to hydroelectric sources below 100MW. The REO and RES both do not count Xcel's mandates from the Prairie Island deals as progress toward the requirement. This remains a signficant additional burden on Xcel which is already the largest purchaser of wind power in the U.S.

The existing statute told the Public Utilities Commission (PUC) to weight different renewable energies (so 2 solar credits might equal 1 wind credit) but that will be scrapped in any impending legislation. The PUC found those instructions cumbersome and lacking proper direction.

The bills revise Minnesota Statute 216B.1691. Let's look the beefed up REO first - S.F. 74.

The new REO requires 5% from eligible sources by 2010. From there, 11% is required by 2013, 15% by 2015, and 25% by 2020.

As before, the PUC has the authority to excuse a utility from meeting the REO if it would cause major problems (like increase rates too much).

The commission must delay or modify the standard for an electric utility if it finds that
compliance with a standard is not in the public interest because compliance will either
produce undesirable impacts on the reliability of the utility's system or on the utility's
ratepayers or if it finds that compliance is not technically feasible.

Subdivision 7 covers the compliance issue:

The commission must regularly investigate whether an
electric utility is in compliance with its standard obligation under subdivision 2a and if
it finds noncompliance must order the electric utility to construct facilities or purchase
credits to achieve compliance. If an electric utility fails to comply with an order under
this subdivision, the commission must impose a financial penalty on the electric utility
in an amount of five cents for each kilowatt hour the electric utility is out of compliance
with its standard obligation.

5 cents per kilowatt hour seems a fairly steep penalty. I could have sworn I heard 5 cents per megawatt hour in an energy committee meeting, but there it is in text. The difference between this new REO and an RES seems minimal given the financial penalty for not meeting. However, there is certainly more room to maneuver under the language of "good faith effort" rather than the RES demands.

The other major bill for consideration is S.F. 4, establishing a Renewable Energy Standard. If I am reading this correctly, it essentially maintains the REO until 2010, then uses the "thou shall" language instead of the "good faith effort" language after that to meet the same goals as above - 11% is required by 2013, 15% by 2015, and 25% by 2020.

As with the REO, the RES ends with a 5 cent per kilowatt hour penalty for each that it is out of compliance.

Given the similarity of the bills, I expect that the debate in the Senate Committee and later on the floor will be over why an RES is necessary when the current REO appears to be working and the new REO will nearly have the same penalties as the RES will.

Update: The RES thread continues with this post.

Small Hydro in Minneapolis

The following was posted on the Minneapolis Issue E-List today from one of the Park Board Members. It refers to a proposal to put a small hydroelectric generation plant on the Mississippi River by the Stone Arch Bridge. I believe that the original proposal was to put it in at the north side of the Mill Ruins parking lot on the west bank.

There is a pretty long history with Crown Hydro. The Park Board denied their previous request for use of park land. There were many issues involved in the decision including concern about stability of the ground above the ruins, noise and vibrations from the turbines, and reduction of water flow. Go to the e-democracy website and do a search for Crown Hydro to find out more. It appears that Crown Hydro has tried to address several of those issues in their latest proposal.

This is a good case of trying to balance the need for increased renewables with the urban environment. St. Anthony Falls is one of the few sites along the Mississippi River that offers any potential for hydroelectric generation. Yet, it's in the middle of the city and a significant historical district. Thoughts?

I have seen a proposal from Crown Hydro that is different from the proposal previously presented to the Park Board.

I am well aware this was a very controversial issue especially for those who live close by.

My District, district # 3 begins down river at Portland, so this project is in my district.

From the proposal:

The power generation will be silent and invisible and operate only when there is sufficient water to keep a minimum amount of water over the falls.


Two silent, vibration free turbines 42' underground; can generate 20-25 Million Kilowathours/year(2000-2500 Homes)


Next to the Park Board's existing water intake for Mills Ruin Park which is located at the North end of the parking lot by the stone arch bridge.


Water enters intake drops 42' passes through turbines hidden below the surface and returns through Park Board tailrace canal in Mill Ruins Park (less than 8% annual river flow)


Turbines operate only when river supplies adequate water. Turbines reduce or suspend operation to ensure flow over St. Anthony Falls and to maintain aesthetics and property values.

They have also suggested that Condo Associations and Neighborhood Groups be represented on a citizen Advisory Committee which would recommend policy about flow rates and make recommendation about some of the revenue produced by this project.

I have many questions, some answers, and would like to make sure this proposal receives sufficient public review.

Rob Brown is their communications person and could provide additional

details: _robbrown12@aol.com_ (


Scott Vreeland

Minneapolis Park and Recreation Board

Commissioner District # 3

UPDATE: An article appeared in the Skyway News on the Crown Hydro project. This will be receiving a lot more attention once the election is over and the Park Board prepares to hear it. I'll try to pass on information when I get it.

Report from U of M Renewable Energy Workshop Oct. 12

I attended the Renewable Energy Workshop today sponsored by the U of MN Electrical Engineering Department. As expected, it was largely technology-focused, with some general discussions of the challenges facing renewable energy here and elsewhere. (And a good buffet style lunch). Here a few salient points of the talks I attended.

A Power Grid for the Hydrogen Economy - Thomas Overbye, U of Illinois

The speaker talked about his research into superconducting transmission lines. The idea behind the project is to supplement our existing grid with a network of underground high voltage DC transmission lines made with superconducting material. The benefit of using superconductors is that the current density can be much higher, so fewer transmission lines have to be built. Line losses would also be minimized.

Each line would consist of a superconducting core for carrying the electricity with an outer ring of liquid hydrogen, which would act both as a coolant and an energy storage mechanism. During times of low electricity demand, excess electricity from renewable sources would be used to create the hydrogen via electrolysis.

Though such a grid is technically feasible, cost is a major issue, though the speaker was quick to note that anything transmission related is expensive. He quoted a figure of roughly $2.5 million per mile to install these cables. Water scarcity may also be an issue in some places.

Lessons from Norway - an unlisted speaker, didn't get his name

(A grad student actually did this talk in place of his professor, who was scheduled to speak but couldn't make it.)

This talk mainly focused on the challenges facing Norway in meeting its future electrical demand and making use of its vast renewable energy potential (enough to supply twice that of its current annual consumption.) Currently, 99% of Norway's generation comes from low cost hydropower. However, similar to here, demand is outpacing supply. More supply will have to be brought on in coming years.

I was struck by how similar the challenges facing renewable energy are to here - public resistance (in the case of wind), cost (wind energy is still more significantly more expensive than hydropower), and political uncertainty (will subsidies continue?) Norway is also facing transmission limitations, just like here.Especially of note is that public resistance to wind energy projects has increased in recent years, for all the typical reasons - avian mishaps, other wildlife impacts, and aesthetics.

Planning for Renewable Energy at a MN Utility - Glen Skarbakka, Mgr of Resource Planning, Great River Energy

The speaker talked about the challenges of meeting GRE's rapidly growing load (about 100 MW/year) while incorporating renewables. GRE's load is mostly residential, meaning that demand goes way up in the summer, but varies a lot day to day, depending on weather. This makes it a challenge to use wind energy, which is not dispatchable in the traditional sense (though forecasting has gotten highly accurate.)

I was mostly impressed by GRE's goals to reduce its CO2 emissions to 2000 levels by 2020, as well as doubling its renewable objective of 10%. The speaker admitted that meeting the first will be extremely challenging, to say the least.

Wind Energy - Present Projects and Potential in Minnesota - John Dunlop, American Wind Energy Association

The speaker talked about how wind turbine technology has advanced over the last 20 years and how wind energy continues to grow rapidly in the US and elsewhere. He also provided a nice summary of the recent situation with the Dept of Defense blocking new wind farms due to concerns over radar. The report finally came out on Sept. 27, 143 days late. It didn't really say anything that could not have been written in one day - only that wind farms can interfere with radar. It didn't offer any mitigation measures to help current or future projects move forward. Sounded like a great use of taxpayer dollars.

Update on CapX 2020 - Terry Grove, GRE

The CapX project is an ongoing transmission planning project involving all major utiltiies in Minnesota, planning transmission needs through 2020. I already knew how long this process takes, but the uninitiatied would probably be shocked. Though, there are good reasons it takes this long. The Certificate of Need process for the first group of lines, mainly to improve reliability, alone will take through 2008. Then route permits have to be aquired, which will take through 2010. During this time, lots of meetings are held with city governments, landowners, and other agencies. The proposed Brookings -SE Minnesota line alone will require that 200,000 landowners be notified. This is just a massive undertaking.

From what I've heard, the last round of tranmission construction was an extremely drawn out and painful process. It will be even worse this time around, due to the industry restructuring that has occured since then. Now, independent power producers can bid in new projects to the MISO queue. Most of these projects fail to get off the ground, since banks won't supply the financing until a power purchase agreement is signed - a chicken and egg problem - meaning that planners don't know where new generation will actually be.

Results of Research Funded by NSF, Xcel Energy, and ONR - Ned Mohan, Electrical Engineering, U of MN

Ned gave an overview of renewable energy-related research in the EE department, then talked mainly about a matrix converter his research team developed. The converter can be used with any variable speed generator, including wind turbines and will boost power output by 1.5X of nameplate ratings. This would also eliminate the problem of bearing currents in typical motors, which eventually destroy the bearing and represent a major maintenance headache. Ned also talked about the benefits of using silicon carbide (SiC) in power electronics, which improves device performance by 10-100 times over plain silicon (Si). The cost of SiC continues to fall, making the use of this material more feasible.

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