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On Hurricane Sandy, Smart Grids And Advanced Storage Technology

If I'm not mistaken, the battery systems you're referring to can offer power for a household for 24 hours, max. And what if the power goes out for a week?

Kimi Arima
Wärtsilä Power Plants

November 5, 2012    View Comment    

On Energy Storage must be supported in the Energy Bill

Willem,

this is exactly what Smart Power Generation is all about. Firstly, extreme operational flexibility (less than 5 min from start to full load, 1 minute to shutdown, 5 minute minimum downtime ==> from full load to shut down to full load in less than 11 minutes) means spinning reserve is, basically, no longer required. Secondly, multi-unit approach means that part-load operation has a minimal effect on efficiency.


Best regards,
Kimi Arima, M.Sc.(Eng.)
Wärtsilä Power Plants
www.smartpowergeneration.com

October 24, 2012    View Comment    

On Energy Storage must be supported in the Energy Bill

Good post, nice listing of all the technologies. However, you could clarify a bit the difference between load shifting with large-scale energy storage (basically, pumped hydro), and frequency regulation with short term, fast response storage (flywheels, capacitors, batteries, etc). For instance, the Beacon Power facility in NY: it can generate 20 MW of power, but only for 15 minutes. On the other hand, macro wind patterns are on the scale of days, so the capacities required are measured in GWh, not MWh. Currently, pumped hydro is the only proven technology that can provide GWh levels of storage. And even though we're seeing very quick development in the technologies you mentioned here, we're talking of a 10^3 difference in scale between what's available and what's needed. Even the German WWF noted in a recent study that there won't be a market for non-hydro energy storage before 2030. From that point of view, it could be argued that the government has plenty of time to legislate yet.

Summa summarum: I agree with your point (support for storage), but not with the timescale.

Kind regards,
Kimi Arima
Wärtsilä Power Plants
www.smartpowergeneration.com

October 23, 2012    View Comment    

On Wind Energy CO2 Emissions Reductions are Overstated

I agree with you on O&M. Nevertheless, Wärtsilä has some very nice references in North America, and the tide might be turning, at least in states with a lot of installed wind capacity. 

I'd venture a guess and say that moving downstream and into the generation business has been considered at the highest levels at Wärtsilä, but that would perhaps necessitate an entirely different set of competencies, one that might not be so easily acquired. 

Enjoyed the chat, wish you a nice weekend. Best regards, Kimi Arima

July 6, 2012    View Comment    

On Negative power prices in RTO and bilateral power markets

In a market situation, the levels of demand and generation dictate the price, and it is against this price that individual producers make the decision whether to operate. If a decision was made that only electricity generated from e.g., wind and solar could be stored, that wouldn't shift the demand nor the economics of the situation. Rather, what would happen is that the wind and solar would then be stored in the form of hydro, and the steam power plants would still be kept running on full load. 

Incidentally, this is what happens in Denmark quite a lot. They have lots of CHP capacity that can't be ramped down past a certain point because heating is required around the clock. Consequently, on some days a vast majority of their wind generation is exported - at a loss - to Norway and Sweden to be stored in their hydro reservoirs. 

Coming back to the original problem, one working solution would be to tilt the cost comparison between operating at full load on a slight loss and operating at partial load at lower efficiency slightly in favor of the latter option. This could be achieved with, among other options, a high enough carbon price. 

July 6, 2012    View Comment    

On Wind Energy CO2 Emissions Reductions are Overstated

A study by Black & Veatch a while back showed that for intermediate and peaking operating profiles (< 5000 hours per year), gas-fired combustion engine plants beat any OCGT plant in lifetime feasibility. This is just not a well-known fact, as the "standard" approach for energy consultancies is to test feasibility on the assumption of 8000 hours per year base load operation (and why not, since all GTs behave rather similarly in cyclic operation, and combustion engines are usually not considered as an option).

Regarding pure base load plants, you are correct, modern CCGTs are the most efficient solution. However, looking at recent developments in some Western countries, it is uncertain how much of pure base load capacity will be required. For instance, Spanish utilities built vast amounts of CCGT capacity during the last decade, but due to the increase of wind and solar, the average capacity factor for these brand new, very efficient CCGTs now sits around 30%. In private discussions some utility people have confided that they're incurring heavy losses and only running the CCGTs because of take-or-pay gas contracts. 

Regarding capacity, 1/4 of Wärtsilä's installed base is in power plants. And, regarding the common conception of "diesel engines": nowadays a majority of the engines Wärtsilä sells for power plants are gas-fired.

July 6, 2012    View Comment    

On Negative power prices in RTO and bilateral power markets

As counter-intuitive as it sounds, energy storage may also increase CO2 emissions. This is happening in some countries with plentiful pumped hydro capacity, where the large steam power plants refrain from ramping down during times of low demand. Instead, the excess electricity is stored in the form of hydro.

Again, this is a natural result of the economics involved: if the cost of ramping down, in terms of lost efficiency and thus greater fuel consumption per kilowatt-hour generated, is greater than the loss taken by producing at full output and selling at market price, of course the producer will keep running on full load. In terms of emissions, however, this is far from optimal. 

Ironically, power system modellings show that in such a system emissions could be reduced simply by reducing storage capacity.

 

July 6, 2012    View Comment    

On Negative power prices in RTO and bilateral power markets

Dear Michael, 

interesting analysis. I would presume that the fossil-fired steam plants be coal, for two reasons: (1) the marginal cost of generation for a gas-fired power plant is considerably higher than that of coal; and (2) shutting down and starting up a (modern) gas-fired power plant takes, say, 1/8 of the time it takes for a coal power plant (so there is less of a risk of lost revenue while offline).

Negative pricing is an interesting phenomenon, and I think one that we're going to see a lot more often in the coming years as our use of intermittent renewables increases. For instance, on the back of a strong increase in wind and solar in the last couple of years, negative prices have become a permanent feature of the German electricity market. 

Not that there's anything wrong with negative pricing - as you said, it's only the market functioning as it's supposed to. Just a new situation that the market players will need to get accustomed to.

Kind regards, Kimi Arima

July 5, 2012    View Comment    

On Wind Energy CO2 Emissions Reductions are Overstated

Hi all, 

interesting discussion. I must, however, point out that there is an established alternative to using OCGTs for wind balancing, namely, combustion engines. A modular power plant based on a multi-unit approach yields superior part-load efficiency, as individual units can be shut down and started up regardless of the other units, and all bar one of the units running can be running on full load. 

Moreover, from start up to full output takes less than 5 minutes for a combustion engine, further reducing the efficiency penalty of cyclic operation. Finally, combustion engines exhibit little to no additional wear and tear from starts/stops and cyclic operation. For instance, there's a 200 MW plant in Colorado, US, called Plains End, that gets hundreds of starts and stops annually, yet shows little additional cost in maintenance. 

If you'd like to know more on the subject, we published a book on this about a year ago, a free PDF version of which is available on our website www.smartpowergeneration.com. 

July 5, 2012    View Comment