Valuing Flexibility: The case of an Integrated Gasification Combined Cycle Power Plant

In this paper we analyze the valuation of options stemming from the flexibility in an Integrated Gasification Combined Cycle (IGCC) Power Plant. First we use as a base case the opportunity to invest in a Natural Gas Combined Cycle (NGCC) Power Plant, deriving the optimal investment rule as a function of fuel price and the remaining life of the right to invest. Additionally, the analytical solution for a perpetual option is obtained. Second, the valuation of an operating IGCC Power Plant is studied, with switching costs between states and a choice of the best operation mode. The valuation of this plant serves as a base to obtain the value of the option to delay an investment of this type. Finally, we derive the value of an opportunity to invest either in a NGCC or IGCC Power Plant, that is, to choose between an inflexible and a flexible technology, respectively. Numerical computations involve the use of one- and two-dimensional binomial lattices that support a mean-reverting process for the fuel prices. Basic parameter values refer to an actual IGCC power plant currently in operation.

Lantern spillway and hydroelectric plant, Panama Canal (ca. 1914)

Leonard Carpenter Panama Canal Collection. Photographs: Dredging, Soldiers, and Ships. [Box 1] from the Special Collections & Area Studies Department, George A. Smathers Libraries, University of Florida.

Mapping and Distribution of Torpedograss and Evaluating the Effectiveness of Torpedograss Management Activities in Lake Okeechobee, Florida

Thousands of hectares of native plants and shallow open water habitat have been displaced in Lake Okeechobee’s marsh by the invasive exotic species torpedograss ( Panicum repens L.). The rate of torpedograss expansion, it’s areal distribution and the efficacy of herbicide treatments used to control torpedograss in the lake’s marsh were quantified using aerial color infra red (IR) photography.(PDF has 6 pages.)

Manual Control of Phragmites australis on Pondshores of Cape Cod National Seashore, Masachusetts, USA

The non-native, invasive genotype of the common reed ( Phragmites australis (Cav.) Trin. ex Steudel) has become a problem of significant proportions throughout wetlands of North America (Saltonstall 2001). Although attempts to suppress or eradicate Phragmites have utilized a wide variety of techniques, herbicides have generally been most effective (Marks et al. 1994). In the spring, mid-summer, and late summer of 2003, we attempted to opportunistically control Phragmites in five freshwater ponds within Cape Cod National Seashore (CCNS) by repeatedly severing stems underwater, at ground level.(PDF has 4 pages.)

Phylogeography and non-invasive landscape genetics of the European pine marten ("martes martes" L. 1758) : insights into ancient and contemporary processes shaping genetic variation

283 p. : graf., map.

Comparative Response of Two Hydrilla Strains to Fluridone

Experiments were conducted in a controlled-environmental growth chamber to evaluate the response of two strains of the invasive submersed plant Hydrilla verticillata (L.f.) Royle to fluridone (1-methyl-3-phenyl-5-[3-trifluoromethyl)phenyl]- 4(1H)-pyridinone). (PDF has 6 pages.)

Comparison of Torpedograss and Pickerelweed Susceptibility to Glyphosate

Torpedograss (Panicum repens L.) is one of the most invasive exotic plants in aquatic systems. Repeat applications of (N-phosphonomethyl) glycine (glyphosate) herbicides provide limited control of torpedograss; unfortunately, glyphosate often negatively impacts most non-target native species that grow alongside the weed. This experiment studied the effect of glyphosate on pickerelweed (Pontederia cordata L.), a native plant that shares habitats with torpedograss. Actively growing plants of torpedograss and pickerelweed were cultured in 8-liter containers and sprayed to wet with one of four rates of glyphosate: 0%, 0.75%, 1.0%, or 1.5%. Each treatment included a surfactant to aid in herbicide uptake and a surface dye to verify uniform application of the treatments. All herbicide treatments were applied with a backpack sprayer to intact plants and to cut stubble of both species. Four replicates were treated for each species-rategrowth combination during each of two experiment periods. Plant dry weights 8 weeks after herbicide application suggest that torpedograss was effectively controlled by the highest rate of glyphosate applied to cut stubble. Pickerelweed was unaffected when the highest rate of glyphosate was applied as a cut-and-spray treatment. These data suggest that a cut-and-spray application of a 1.5% solution of glyphosate may be an effective strategy to control torpedograss without deleteriously affecting pickerelweed. (PDF contains 4 pages.)

Physical Constraints to Aquatic Plant Growth in New Zealand Lakes

The nature of aquatic plant communities often defines benthic habitat within oligotrophic and mesotrophic lakes and lake management increasingly recognizes the importance of maintaining plant diversity in order to sustain biological diversity and capacity within lakes. We have developed simple statistical relationships between key physical and vegetation variables that define the habitat requirements, or “habitat-templates”, of key vegetation types to facilitate management of plant communities in New Zealand lakes. Statistical relationships were derived from two datasets. The first was a multi-lake dataset to determine the effects of water level fluctuation and water clarity. The second dataset was from a comprehensive shoreline survey of Lake Wanaka, which allowed us to examine within-lake variables such as beach slope and wave action. Sufficient statistical relationships were established to develop a habitat template for each of the major species or assemblages. The relationships suggested that the extent and diversity of shallow-growing species was related to a combination of the extent of water level fluctuation and wave exposure. (PDF contains 9 pages.)

Potential use of remote sensing to assess effects of wave action on plant re-establishment

Evaluation of the potential for remote sensing to detect a relationship between wave action factors and plant re-establishment after a habitat enhancement at Lake Kissimmee, Florida. Using Geographic Information Systems (GIS) and remote sensing, wave action factors were found to be inversely related to the probability of plant re-establishment. However, correlation of wave action factors with areal coverage of aquatic plants based on field measurements, were unable to detect a significant relationship. Other factors aside from wave action, including littoral slope and the presence of offshore vegetation, may have influenced plant re-establishment in these sites. Remote sensing techniques may be useful to detect large changes in plants communities, however small changes in plant coverages may not be detectable using this technique.

Endothall species selectivity evaluation: northern latitude aquatic plant community

Species selectivity of the aquatic herbicide dipotassium salt of endothall (Aquathol® K) was evaluated on plant species typically found in northern latitude aquatic plant communities. Submersed species included Eurasian watermilfoil (Myriophyllum spicatum L.), curlyleaf pondweed (Potamogeton crispus L.), Illinois pondweed (Potamogeton illinoensis Morong.), sago pondweed (Potamogeton pectinatus L.), coontail (Ceratophyllum demersum L.), elodea (Elodea canadensis Michx.) and wildcelery (Vallisneria americana L.). Emergent and floating-leaf plant species evaluated were cattail (Typha latifolia L.), smartweed (Polygonum hydropiperoides Michx.), pickerelweed (Pontederia cordata L.) and spatterdock (Nuphar advena Aiton). The submersed species evaluations were conducted in 7000 L mesocosm tanks, and treatment rates included 0, 0.5 1.0, 2.0, and 4.0 mg/L active ingredient (ai) endothall (dipotassium salt of endothall). The exposure period consisted of a 24-h flow through half-life for 7 d. The cattail and smartweed evaluation was conducted in 860 L mesocosm tanks, and the spatterdock and pickerelweed evaluations were conducted in 1600 L mesocosm tanks. Treatment rates for the emergent and floating-leafed plant evaluations included 0, 0.5, 2.0 and 4.0 mg/L ai endothall, and the exposure period consisted of removing and replacing half the water from each tank, after each 24 h period for a duration of 120 h. Biomass samples were collected at 3 and 8 weeks after treatment (WAT). Endothall effectively controlled Eurasian watermilfoil and curlyleaf pondweed at all of the application rates, and no significant regrowth was observed at 8 WAT. Sago pondweed, wildcelery, and Illinois pondweed biomass were also significantly reduced following the endothall application, but regrowth was observed at 8 WAT. Coontail and elodea showed no effects from endothall application at the 0.5, 1.0, and 2.0 mg/L application rates, but coontail was controlled at 4.0 mg/L rate. Spatterdock, pickerelweed, cattail, and smartweed were not injured at any of the endothall application rates.

Presidential Address: The Aquatic Plant Management Society and Our Future Sphere of Influence

Presidential address of Alison M. Fox