Is Hovensa Power Plant More Efficient Than WAPAs?

Considering everything. LNG is the right way to go. Converting the STG boilers (or combustion turbines) from Fuel Oil to NG (or duel fuel) should not be all that costly. And the emissions would be lower. However, the cost would be in the LNG unloading terminal and the on-island storage facility. LNG needs to be refrigerated including the storage. We need a developer or utility with some borrowing power.

WAPA has about a 60%- 40% Split between Gas Turbine (Frame 5 GT) and Steam Turbine Units. Hovensa has the latest and greatest version of the Frame 5 and about 35% Steam. Both the WAPA STX Plant and Hovensa have WHB's. The stated GE Thermal Efficiency for the GT's are 37% @ 18MW on distillate fuel. The actual thermal efficiency of WAPA on a total fuel basis is stated (By DOI, EIA) at roughly 24%. Then there's the line loss, theft, systemic excursions as part of a lack of maintenance and repair. I figure that's another 8% loss of
efficiency.

Then we have WAPA's poor operating practices in Boiler Water Management in the Steam Plants, Bad Fuel Rotation Practices and just a generally lethargic maintenance and repair regimen....

The equipment is basically the same, though older in WAPA and poorly maintained. Last month STT suffered a major loss of the #11 Boiler because of the scale and blistering ocurred because of salt water contamination in the boiler feed water- it only takes 100 ppm at 600 psig to do widespread damage. This is one of the reasons that water storage ocurred....

Hovensa is fueled by a mix of distillate and resid fuels and is VERY expensive to "fuel" the refinery. The GT sets can run on LPG- but that commodity is used elsewhere for better financial result. The ONLY way the refinery will reopen I think will be by retooling the plant LNG.

Chief,

If the GTs have WHBs are they using the steam for process or combined-cycle arrangement to drive an STG? In CC arrangement, the combined efficiency should be over 50%.

In any case if the refinery does close, some one should make use of the power equipment to benefit the VI. Otherwise, if goes on the open market, who knows where it will end up. The VI Gov.t should be getting lined up to facilitate this now. WAPA has no money for that type of investment, so it will take an IPP to come in. But then the issues will arise as to what rate will the IPP get paid by WAPA ... and is it enough to justify the costs of an LNG terminal and storage. There would have to be some "deal" up front (...say for Gov.t stability reasons) to avoid the normal WAPA process of RFP for a PPA, since it would drag out for years like what happened on the Alpine project or even the the Solar PV project.

I fgured about 47% on combined, with a lot of the recoop steam going to the disatilling plants. We're still not getting the proper amount of energy out of the energy we're putting in. Something very wrong...

Are you talking net or gross at the generator terminals. A CC plant that gets a +50% efficiency is the gross electric production at the generator terminals. Note, the parisitic load on the steam portion may be as high as 25% of the STG gross output.

Avis newspaper editorial on Thursday has great article on the topic of using power plants for energy on St Croix.

Recommends a private/government psrtnership. Editorial also believes HOVENSA plants use less expensive fuel and are more efficient. Could be part of the solution for energy on St Croix.

All this proves is that Lucy and DaChief are both true 'energy geeks'. 😎
Indulging us commoners a little by elaborating on the process and explaining some acronyms would be very helpful.
I for one don't know WTF a WHB is?

All this proves is that Lucy and DaChief are both true 'energy geeks'. 😎
Indulging us commoners a little by elaborating on the process and explaining some acronyms would be very helpful.
I for one don't know WTF a WHB is?

OK. The WHB = Waste Heat Boiler. That is the Chief's terminology. I would normally use HRSG ... Heat Recovery Steam Generator. HRSG is used on CC plants. Combined-Cycle plants; meaning you have a gas (or in this case a fuel oil) fueled combustion turbine-generator where the exhaust gases go into the HRSG to make steam; that then drives a STG... Steam Turbine-Generator.

I think I know what a WTF is ? Ha ! 😮

I read the AVIS, its definately something the USVI should be inquiring on---and according to the article, WAPA's power plant uses less expensive fuel and has to be more efficient. HOVENSA must know how much its costing per KW?

All this proves is that Lucy and DaChief are both true 'energy geeks'. 😎
Indulging us commoners a little by elaborating on the process and explaining some acronyms would be very helpful.
I for one don't know WTF a WHB is?

OK. The WHB = Waste Heat Boiler. That is the Chief's terminology. I would normally use HRSG ... Heat Recovery Steam Generator. HRSG is used on CC plants. Combined-Cycle plants; meaning you have a gas (or in this case a fuel oil) fueled combustion turbine-generator where the exhaust gases go into the HRSG to make steam; that then drives a STG... Steam Turbine-Generator.

I think I know what a WTF is ? Ha ! 😮

Thanks Lucy - that makes it much clearer. Well about as clear as WAPA water anyway. 😎

(and a good WTF usually needs hand/arm gestures - difficult to do on a forum).

This is based on spot prices listed on Bloomberg today. NG = $3 per MMBTU and Fuel Oil = $3 per gallon.

Assume that buying in bulk lowers the price of NG, but that is cancelled by the liquification and transport of LNG. Also boiler combustion efficiencies are the same.

A gallon of fuel oil has an energy content = 150,000 BTUs.

So it takes 1,000,000 / 150,000 = 6.7 gallons of Fuel Oil or $20 for the same energy content as $3.00 of NG.

Even if the cost of LNG doubles to account for the infrastructure additions, it is a much better deal. The Vi should be finding a way to convert now before the other islands do. Use this plant closure and the VI fiscal crisis to our advantage.

Some on once said, "you should never let a crisis go to waste".

But it might take the Gov., assuming he has some "balls", to proclaim a change by executive order to by-pass the normal slow-mo Gov.t / WAPA process of studies and RFPs and endless evaluations.

Well Lucy- It seems as though you use some standard terms. Are you a Power Engineer? I am. Currently I base all my calcs and figures as follows: (Remember that fuel rates are expressed by pounds because of the gross/net conversion to API 60)

2 Oil= 17000 btu/lb
6 Oil= 19500 btu/lb

WAPA currently burns about 24000 bbls per week at STX- mostly #2 Oil to the GT Sets. I would rate the overall thermal to end user efficiency (thats btu/t to btu/e converted to kwh (@3412 btu/kwh before efficiency). The overall thermal efficiency from "cradle to grave" for STX has averaged about 24% overall (DOI DOE sources) plus I backed this up from the fuel consumed to the actual MWh output.

Now, a Steam Generator of the third generation 20th Century- Non Reheating, Express Type, Modified D, Intergal Superheater, Front Fired, Forced Draft, Accelerated Natural Circulation, 600,000 #/hr, 1200 psig @ 935 F., usually weighs in with an overall plant efficiency of about 33% Thermal.

The stated and public GT Frame 5's, with upgrades to the fuel/governing system usually weighs in at 37% Thermal. Add the WHB or HRSG (forgive me- my background is marine- we still call them waste heat boilers) and I would estimate 42-50% thermal depending on what type of secondary system (no it does not have to be steam/water- I've seen something called thermal oil- no boiling and therefore no 970 btu per pound at saturation)

This STILL does not change the fact that WAPA is probably one of the most inefficient operations ever know in the history of the power plant.

LNG- I see all kinds of comment relative to the fact about infrastructure, ports, terminals, storage and other "salient" points- all bunk!

The refinery has the space, draft, infrastructure and NEED to develop an LNG Hub- NOT facility, a Hub- which will not only solve the insolvency problem in refining by going to a cheaper, cleaner and more attainable fuel- but I will bet within one year will be pipelined direct to WAPA. It's obvious that the current refinery ownership doesn't wish to sink more money into the sink hole- a new owner will be here by October the latest to start retooling. Then WAPA will convert their GT's to NG and life will go on. The reorganization by a "related company" to the current owner stinks to high heaven- but what choice do we have.

Now for the Political end. In July/August- when the kwh cost is approaching .62-.65 per kwh, and gas on STX is 6 bucks a gallon- the Pols and other assorted elected welfare recipients will SCREAM YES for the "new deal". Hopefully we'll all be just onbe wiser and DEMAND a better deal at the bargaining table. It's not personal, it's business- this will also knock the crap out of the consent decree with the emissions reduction.

I believ that this is all part of a well orchestrated plan, one which may be painful at first, but will level out in the end- it will be better for all PROVIDED that kwh cost is around .28 and gas under $3 when it's all said and done.

Listening to 93.5 radio about an hour ago, power line runs from HOVENSA to hospital already. And according to the guest, not a major capital project to feed from this line into the WAPA line. Senators meeting and will be discussing options next week.

Well Lucy- It seems as though you use some standard terms. Are you a Power Engineer? I am. Currently I base all my calcs and figures as follows: (Remember that fuel rates are expressed by pounds because of the gross/net conversion to API 60)

2 Oil= 17000 btu/lb
6 Oil= 19500 btu/lb

WAPA currently burns about 24000 bbls per week at STX- mostly #2 Oil to the GT Sets. I would rate the overall thermal to end user efficiency (thats btu/t to btu/e converted to kwh (@3412 btu/kwh before efficiency). The overall thermal efficiency from "cradle to grave" for STX has averaged about 24% overall (DOI DOE sources) plus I backed this up from the fuel consumed to the actual MWh output.

Now, a Steam Generator of the third generation 20th Century- Non Reheating, Express Type, Modified D, Intergal Superheater, Front Fired, Forced Draft, Accelerated Natural Circulation, 600,000 #/hr, 1200 psig @ 935 F., usually weighs in with an overall plant efficiency of about 33% Thermal.

The stated and public GT Frame 5's, with upgrades to the fuel/governing system usually weighs in at 37% Thermal. Add the WHB or HRSG (forgive me- my background is marine- we still call them waste heat boilers) and I would estimate 42-50% thermal depending on what type of secondary system (no it does not have to be steam/water- I've seen something called thermal oil- no boiling and therefore no 970 btu per pound at saturation)

This STILL does not change the fact that WAPA is probably one of the most inefficient operations ever know in the history of the power plant.

LNG- I see all kinds of comment relative to the fact about infrastructure, ports, terminals, storage and other "salient" points- all bunk!

The refinery has the space, draft, infrastructure and NEED to develop an LNG Hub- NOT facility, a Hub- which will not only solve the insolvency problem in refining by going to a cheaper, cleaner and more attainable fuel- but I will bet within one year will be pipelined direct to WAPA. It's obvious that the current refinery ownership doesn't wish to sink more money into the sink hole- a new owner will be here by October the latest to start retooling. Then WAPA will convert their GT's to NG and life will go on. The reorganization by a "related company" to the current owner stinks to high heaven- but what choice do we have.

Now for the Political end. In July/August- when the kwh cost is approaching .62-.65 per kwh, and gas on STX is 6 bucks a gallon- the Pols and other assorted elected welfare recipients will SCREAM YES for the "new deal". Hopefully we'll all be just onbe wiser and DEMAND a better deal at the bargaining table. It's not personal, it's business- this will also knock the crap out of the consent decree with the emissions reduction.

I believ that this is all part of a well orchestrated plan, one which may be painful at first, but will level out in the end- it will be better for all PROVIDED that kwh cost is around .28 and gas under $3 when it's all said and done.

Chief. I think you may have mis-interpreted me. I was not questioning your assessment on the lower efficiency, but just pointing out what it should be. Yes, the WAPA plants and WAPA have an issue.

I am an engineer (not power process) but have been in the power business (Nuclear, Coal Steam Plants, GTs, Biomass, Solar Thermal, WHB) for over 35 years. I just try to keep it on a high level in order to compare things quickly.

As for the WHB using thermal oil, if they are not using it for power production, then they are using it for process heating. If the need for process heating goes away, then the TO can be used for power production. See this web site.

http://www.adoratec.com/

If you have further interest in ORC, PM me and we can talk.

Thanks Lucy- This weekend...

Some Info on LNG. I knew it had to be liquefied by refrigeration, but never realized they need to keep it at -260F. That would freeze your toes for sure. The process also removes all the impurities, so what you have left is almost pure methane.

http://www.naturalgas.org/lng/lng.asp

And here is where USVI would most likely get it. Tobago is fairly close.

http://www.atlanticlng.com/

In addition, some might know that there is a real boom going on in Ohio, PA and WV to hydro-frac the Marcellus Shale seam to extract NG. To support this, Dominion has proposed to the US Gov.t to build an LNG Process Plant and Export Terminal. Here is one of the large drilling companies that continues to expand big-time.

http://www.rangeresources.com/

But here some not so good news. The price for LNG is about $15 per MMBTU. This is 5 times the price of NG in it's gaseous state. The financial analysts are predicting that to go to $20 per MMBTU. Almost the same as fuel oil - at least without the impurities.

http://www.bloomberg.com/news/2011-09-19/lng-price-boom-seen-as-japan-vies-with-china-while-exxon-s-shipments-grow.html

Another BIG problem is that LNG is "environmental hot button". Google: LNG protests, Hilary Clinton, Malibu paddle out. Most of the oppisiotn has to do with sub-aquatic piping and transfer. Perhaps the current infrastructure (transfer, piping. storage) at Hovensa is well suited to LNG? Re-tooling with little impact? LNG is a cleaner burning fuel. And who supplies the product? I think purchasers pay-up front and are responisble for delivery mechanics. Is that correct? How do the contracts go down?

The other islands (Grand Caymen, Bermuda, etc.) Have gone to medium-speed diesel engine generator plants. These can be set up as duel fuel (oil and NG) and are 45% efficient. With waste heat recovery, this can go to 50%. MAN B&W is providing 4 new units in Bermuda right now that are rated at about 16 MWe each. This might be the best option for the VI going forward.

Lucy- I would even go further...LARGE Slow Speed Diesel Gensets in the 30 to 50 MW range can almost burn anything- combine that with a WHB/HRSG and you would be in business.

The medium speed units that you mention on NG are great, but let's remember one thing- an average Medium Speed Engine has in the neighborhood of 4000 moving parts, the Gas Turbine a lot less. Maintenance (or lack thereof) seems to be the biggest question of why WAPA consistently fails to meet benchmark thermal efficiency- The slow speed concept is probably the most bang for tthe buck...

But, I venture that the fewer the moving parts, the easier the maintenance implications. I personally like Sultzer RTA's, in the 20 mw range- but that's even too much for WAPA to handle. I have been somewhat gifted in the area of foresight- so I'll present this:

WAPA doesn't have the skill set or resources to adequately operate or maintain a large Steam Plant in an overally efficient manner. That's why the new water plants are RO type- the Flash Types are very unforgiving with a lack of maintainance..Not to mention the steam plant that drives them.

The key here is to REMOVE WAPA from the equation and substitute them with an entirely private utility. I have an idea- Now that the refinery is out of the question, we could resurrect the old VIALCO Coal Fired Plant with upgrades and NG Co-Gen, also fit it to burn trash- get the money from the feds- and go on from there- the emissions would still be less than when "the beast" was on line. Scrub Alpine, Scrub a large part of WAPA.....

Chief, you are right on. BEC has 2 slow speed MAN B&W units at their Clifton Pier plant on Nausau. Not sure why BELCO is going with med-speed instead of slow speed. What is the efficiency of the slow speed units? As I mentioned the new MAN med. speed are 45%.

I've been promoting that the VI Gov.t sell the WAPA generation assets to get revenue. Then you get a real utility in there that has deep pockets and the right experience to run / maintain the plants and modernize what is needed. Let WAPA keep the T&D.

There could be an opportunity to convert the Hovensa equipment, but the entity would have to qualify as an IPP. Then there is the issue of what WAPA will pay if it is not their idea.

Best is to wait until things are in crisis mode .... or maybe it is, but the gov.t isn't acting that way .... and maybe things could get fast-tracked. You mention Alpine. They have been screwing around with that for well over 3 years and they still do not have a lease agreement for Bovini and no permit applications submitted.

I think the choice of medium speed is generally easier access to parts and less emissions...

Sulzer's are fun though- less moving parts, some have valves, no camshafts- especially for shoreside apps- the flex rail. Agreed, Crisis Management should be on the back burner, although we shouldn't be dependent on crisis management to push through our latest "alternative" arrangement- that would be foolhardy from the business standpoint...

LUCY AND DACHIEF FOR SENATE!!!!

Already ran for a couple of different offices..Did ok- better than some of the "mainline" candidates- but still missed the mark by a large margin. We're engineers- engineers are problem solvers by nature. Only recently I am finding that leaving emotion out of it and being positive is what is the real order of the day.

I appreciate your support- I have had to reorganize my career recently, and I don't think that running again would be in the cards. I have made my services (gratis) known to many of those in power now- never even got the benefit of a response- so I shelved that idea.

We need to organize a "think tank" for solutions. Not empire building, not based on self preservation, not for monetary gain- just a way out of this economic quagmire..What was said once: "If you keep making the same mistakes, why are you so surprised at the same results?"

No, the time for the blame game, political retribution, lip service politics and all the other hosts of "negative wave production" is over. We NEED answers and we need them quickly.....

Chief - I could not have said it any better or clearer. Thanks !!!