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

- Decem­ber 17, 2014, Before It’s News

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.com
www.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