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Wind & pumped hydro II

Wind & pumped hydro II

Wind & pumped hydro II

(OP)
A large wind farm is going in ~1 mile from an incised river valley with 180 to 200 feet of fall from the surrounding land to the riverbed. Does this represent a viable pumped energy system?

RE: Wind & pumped hydro II

(OP)
Yes, lots of unknowns but one must start somewhere - land availability, soil permeability, electricity cost for pumping, water availability, etc. Would 12,000 acre feet at 200' of head make pursuit worthwhile? Can find nothing similar in the Midwest. The closest in concept is a proposed compressed air system with underground storage. They build anaerobic lagoons in the area so soil permeability can probably be dealt with.

Who has the check-sheet for feasibility or rules of thumb?  

RE: Wind & pumped hydro II

It would seem to me that the math is quite simple from a hydraulics point of view, pump curves and hydro curves are well known. If the windfarm is going in then they know the energy output, they also should know the off peak energy sale cost which is what makes a pump storage viable. A good energy/power consultant should be able to advise the economics and feasability quite quickly.

RE: Wind & pumped hydro II

I've never understood how wind power generation ever got mixed up with off peak pumped storage.  Power generation is power generation, doesn't matter if its wind/water/coal/etc...  The pumps requier 'x' amount of power to pump the water.  

In most cases politics also creates the situation where you are almsot always better selling your wind power to the grid (premiums on wind power gnereated power).  If you get a premium on the wind power you sell to the grid why would you want to use it yourself?  Sell the power from the wind farm to the grid if possible, and use that money to offset the cost of running the pumps.    

RE: Wind & pumped hydro II

marks; There are many places that get stiff wind after dark and late into the night when no power is needed.  You would want to pump then.

 

Keith Cress
kcress - http://www.flaminsystems.com

RE: Wind & pumped hydro II

It's all a matter of economics. Look at the rates you get for power when it's windy and when it's not vs. the cost and losses of the pumped storage. Don't forget the opportunity cost of the capital in your life cycle cost calculations.

Alan
----
"It's always fun to do the impossible." - Walt Disney

RE: Wind & pumped hydro II

My first response would be, this is certainly worth loking into. In some instances the best efficiency combined with the simplest control scheme may be achieved by dedicating the wind power to pumping water. The wind turbine control would be optimized to pump the most water possible.
A separate hydro turbine would then use the pumped water to generate power as needed.
Yes this system needs two hydraulic machines, rather than a combined pump/turbine, but the pump may be optimized for pumping and the turbine may be optimized for generation.
Intriguing. I know a similar but more challenging site on an island now supplied by diesel power. I have been suggesting a preliminary feasibility surrey but I can't get anyone in authority interested.  

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Wind & pumped hydro II

Quote:

In some instances the best efficiency combined with the simplest control scheme may be achieved by dedicating the wind power to pumping water.
I tend to agree with marks1080.  Wind turbines have no fuel cost, so why not generate whenever the wind is in the favorable speed range instead of only when you need to pump water?

Let's say you're at full pond, the wind's blowing, and energy rates are at peak.  You would want to be using both the hydro and the wind turbines, but you wouldn't want to be pumping water.
 

RE: Wind & pumped hydro II

All these people that are pooh-poohing the idea apparently don't understand that the electric market can go negative at times of high generation and low demand.  Why "sell" into a negative market?  There may be times that it makes the most sense to use the wind output and all the additional power you can buy to pump water.

The real beauty of a combined wind/pumped storage plant is that it can be dispatched, while wind alone is too unpredictable for long term dispatching.  Wind won't really be taken seriously in large quantities until/unless it can be reliably firmed up.  Batteries just aren't there, much of the country doesn't have enough hydro, and combustion plants don't like the sudden load swings associated with firming wind.  Pumped storage hydro is the best available means of firming wind power.

RE: Wind & pumped hydro II

(OP)
     National Hydropower Association's comments regarding Chu's comments on pumped power - http://hydro.org/news/Chu%20pumped%20storage%20statement.pdf
     Don't know enough to factor efficiencies into theoretical calculations so extrapolated from the Salilna Pumped Storage Project in Oklahoma. 100 MW for 6 to 12 hours seems feasible which is the proposed production capacity of the wind farm.  

RE: Wind & pumped hydro II

If I recall the GRDA in Oklahoma also has several hydro-electric plants which can be dispatched in conjunction with wind. And while they don't have any pumping ability, they could be dispatched agenst native load. However, river flows would have to be consitered in the mix.

While this may be specific, it can be generaly be applied to several hydroelectric instalations.

 

RE: Wind & pumped hydro II

I believe the future of wind power lies with policy makers.  The region where I work, wind power is actually classified as 'non-dispatchable' generation, and the rates paid for wind power are far and above anything you would ever get from hydro or fossil.  

That being said, if you have a pumped storage set up and you have a wind gereration set up all you really need to do is make sure each system is as efficient as possible.  Wether or not they are directly connected doesn't make that much of a difference.  I would actually anticipate problems for the pumps if the only power supply they had was from wind power.  

Yes wind potential is much higher in the night than in the day, and that is also when you would use pumped storage. Whether or not you are getting less money per kilowatt by selling to the grid at night or you are paying less for power to run your pumps at night all works out in the wash.  

david:  Have you heard of wind power/hydrogen cogen set ups?  I think they have a lot of potential towards 'firming' up wind power.   

RE: Wind & pumped hydro II

marks; Is the hydrogen generated electrically(electrolysis) as the storage media?

Keith Cress
kcress - http://www.flaminsystems.com

RE: Wind & pumped hydro II

(OP)
There is a huge need for hydrogen in the Midwest for the production of anhydrous ammonia for use as a plant fertilizer AND potentially as a direct fuel. Yes, a fuel - http://www.energy.iastate.edu/Renewable/ammonia/index.htm . The UP has a locomotive running on anhydrous ammonia and the ag sector could be converted to run on hydrogen based anhydrous relatively easily. Anhydrous is being used in irrigation pump systems in CA because it meets their clean air requirements. Anhydrous ammonia plants run on hydrogen from natural gas.

There is a second looming need for hydrogen – the upgrading of biooil created by the fast pyrolysis of agricultural biomass to fungible fuels. DOE says that upgraded biooil could meet 60% of the US transportation fuel needs..

Any suggestions on engineering companies that could undertake a statewide evaluation of the feasibility/usefulness of pumped hydro?
 

RE: Wind & pumped hydro II

I would think there are less expencive ways to derive hydrogen than electrollis of water. But what do I know steel balls and hydrocloric acid sounds good to me (HCl + Fe = FeCl + H2).

The fact wind power is more expencive and ocures during off peak, should be a sign that it is not a very good idea.
And I admit there are some special cases, like remote sites with batteries, and backup power.

 

RE: Wind & pumped hydro II

itssmoked:  Yes electrolysis

cranky108:  Your points go against your argument.  The fact wind power is most effective during off peak hours is exactly why its a good idea to use it to power an electrolyzer for H2 production.  Atleast that way you don't need to buy/store steel balls and acid...  Not to mention find some place to dump the FeCl.

I studied a pilot project on this wind/hydrogen co-gen that was happening in Newfoundland.  For those of you that don't know Newfoundland is an island (geogrpahically and electrically).  There are a lot of small communities that run off diesel gen sets.  The wind/hydrogen cogen site is intended to drastically cut back on the amount of diesel needed (wind is sounding cheaper now right?). During high demand periods when there is wind available, the wind turbine just supplies the load.  When there is wind but low demand, the wind turbine supplies the electrolyzer.  When there is high demand and no wind, you burn the hydrogen to create power.

Personally, I think every wind farm should have something like this.

RE: Wind & pumped hydro II

So after the water falls into the canyon, it is pumped back uphill for storage. Why not simply keep it at the top of the hill in the first place, avoiding all the energy used in pumping? All you need is a dam. Then the wind can be left to move people and their toys around on the water as a form of recreation.

RE: Wind & pumped hydro II

The idea to store temporarily unsellable wind power in an elevated lake is sound but 200 feet is a little low for a PHES plant.
The important formula is; power [kW] = flow[m3/sec]*head[m]*9
Example; 100MW = 55.5m/sec. * 200M * 9
It is as simple as that.
 

RE: Wind & pumped hydro II

Assuming that you live in an area with an integrated supply grid, it makes no sense to build a pumped-storage plant especially designed for a wind farm. The energy supplied by the wind farm mentioned can be utilized by the consumers around and the surplus energy can be utilized by any other pumped-storage plant connected to the grid.

The combination of wind power and pumped-storage, however, can be favourably realized on an island. There are some projects under review in Greece.

Regards

Wolf
WWW.HYDROPOWER-CONSULT.COM

RE: Wind & pumped hydro II

(OP)
Thanks for everyone's comments, relevant or not. Concluded that 200' in this situation isn't viable. Didn't find any pumped hydro under ~280'. Could increase flow to account for lower head but that requires more turbines/pumps – so greater capital equipment and operating costs. As pumped volume increases, the percentage of river water being consumed and the peak flows back into the river starts to create environmental issues. Looked for and found an off-site viable pumped hydro site a state away. But you have to create the grid infrastructure to the site; and transmission losses and transmission costs are not insignificant.

If I was a consultant in this area, I'd create a simple section on a web site that summarizes the issues and use it to drive business development and minimize – questions. I never found such and now know that my original question could be boiled down to a few questions to which a few rules of thumb are applied.
 

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