Questions of Reliability at Gainesville, Florida’s Biomass Generator Raises Concerns

- December 17, 2014, Before It’s News

[[{"type":"media","view_mode":"media_large","fid":"359","attributes":{"alt":"","class":"media-image","height":"283","style":"width: 333px; height: 228px; margin: 3px 10px; float: left;","width":"413"}}]]In December 2013, the GREC Biomass generator was taken off-line to install noise-absorbing panels inside the main stack in an effort to quiet numerous noise complaints from residents living in Turkey Creek and surrounding communities. Even while noise and dust complaits continue, GRU/GREC, the City of Gaiesville and Alachua County have closed public access to log local complaints – requiring citizens to file complaints in the on-responsive vacuum of the State environmental protection department.

Through public records access, it’s now revealed that defective equipment at the GRU/GREC biomass generator was reported only a few months after the down-time required for noise abatement -  a revelation that has only recently come to light for public notice and GRU ratepayer review.

By GRU’/GREC’s s own estimate, the off-line time required to correct the defective parts could save GRU ratepayers $160,000 per day or a total of $2.2 million dollars.

The non-emergent nature of the repair is due to the substantial glut of low-cost alternative energy sources at GRU’s Deerhaven facility and purchase options around the state.

In a letter From GRU General Maager, Kathy E. Viehe to Gainesville City Commission Commission – Note the problem with the defective boiler was apparently noticed to the Commission back in May 2014.

Mayor and Commissioners,

Attached is a letter Mr. Stanton received last week from GREC in regard to a mechanical issue with the GREC plant.  In January they will take a forced outage to repair the leak, and then, as you will read in the letter, in April, during their planned outage, they will perform more extensive repair work. We see no adverse impact to GRU at this time: In the short term, we have adequate replacement generation for each day GREC is unavailable beyond their original outage schedule. Based on the contract, we will save the Available Energy Charge. While we will likely need to replace GREC with higher variable cost generation, the estimated net savings to GRU should be around $160,000 per day. The very preliminary estimate by GREC is that they will need an additional 2 weeks of outage time, so that’s an estimated savings of over $2.2 million. All costs are to GREC and by warrantee to Valmet, the boiler manufacturer.
 
Please feel free to contact Mr. Stanton who would be more than happy to provide a technical description of the problem should you desire it.
 
Best Regards,
Kathy
 
Kathy E. Viehe
Interim General Manager
GRU (Gainesville Regional Utilities)
PO Box 147117
Gainesville, FL 32614
352-393-1035
vieheke@gru.comwww.gru.com

____________________

This recent December 11 report was outlined in a letter from GREC Asset Manager,  Leonard J. Fagan -  Vice President of Engineering although the defect was quietly acknowledged back in May of this year.

December 11, 2014 – Mr. John Stanton,
Assistant General Manager, Energy Supply
Gainesville Regional Utilities
301 S.E. 4th Avenue
Gainesville, FL 32614-7117
Subject: April 2015 Outage and Tertiary Superheater Issue

Dear John:

As you know, in May 2014 we had problems with the boiler tertiary superheater resulting in a tube failure and a number of weld cracks. During the October 2014 outage inspection additional cracks on a number of tubes were discovered. All these issues were repaired per proper procedures and the boiler is in operation.

GREC and Valmet have reviewed the failures, conducted metallurgical examinations and have completed a root cause analysis (RCA). Investigations included base material for the P91 header and T23 tubes, manufacturing, and a failure cracking mechanism using finite stress analysis. The conclusion of the RCA is that the failure mechanism is a combination of creep and fatigue.

Valmet’s recommendation is to replace the header complete with nozzle tubes, making them from grade
T24 rather than T23 material. The new design has added flexibility to reduce stress levels. The design is now completed. The new header material procurement is underway and Valmet is currently meeting with fabricating facilities to obtain pricing and schedule. We are waiting for an updated schedule from Valmet to support the target date of April 1st at the site and will be meeting with them on January 8th to review. The intent of this letter, in addition to providing an update on the superheater issue, is to request a modification to the April outage. At this time we believe the original planned two week outage will need to be extended to four weeks, which is worst case. After our January review meeting and the selection of the installation contractor this may be reduced.

Sincerely,


Leonard J. Fagan

Vice President of Engineering

GREC Asset Manager


LJF/ctw