DOC PREVIEW
MIT 1 011 - SEVERN TIDAL POWER

This preview shows page 1-2 out of 6 pages.

Save
View full document
View full document
Premium Document
Do you want full access? Go Premium and unlock all 6 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 6 pages.
Access to all documents
Download any document
Ad free experience
Premium Document
Do you want full access? Go Premium and unlock all 6 pages.
Access to all documents
Download any document
Ad free experience

Unformatted text preview:

1.011 Project Evaluation Spring Term 2003Libby Wayman, Michael Star, Ana Albir Page 1SEVERN TIDAL POWERp. 276, CharlierScience Behind Tidal Power• Tide definition: “The tidal phenomenon is the periodic motion of the waters of the sea, caused by celestial bodies, principally the moon and the sun, upon different parts of the rotating earth” (Charlier 75).• The sun’s contribution to these forces, however, are negligible compared to that of the moon.• Although tide-producing forces are distributed evenly over the globe, variations on size and shape of ocean basins, as well as the interference produced by land masses create differences in actual tidal current.• The tidal patterns of a certain area are determined by its location in a certain basin.http://power.about.com/gi/dynamic/offsite.htm?site=http%3A%2 F%2Fwww.iclei.org%2Fefacts%2Ftidal.htmAScience, continued• Tidal current is the horizontal flow of water accompanying the vertical movement of the tide. • Tidal amplitude, the difference between high and low tide, is a key factor in determining the energy output of a power plant.• Barrage is the damming part of the plant, although generally must be much stronger than a regular dam due to stress from waves (and, therefore, adds quite an expense).• The cost per kilowatt drops with the size of turbine.• The typical “bulb” turbine (used at the Rance tidal plant) also functions as a pump and regulates the flow in both directions.History of Tidal Power at Severn• First projected in 1918, but ridiculed.• After end of WWII, thirst for energy revived interest in tidal power.• The Severn River, near the Bristol Channel, has the largest tidal difference in Europe.• Although vetoed by Parliament, hindsight reveals that a plant built in 1949 would have more than paid for itself in ten years, and had negligible costs afterwards.Severn as a Possible Site• Severn River estuary has 3rdgreatest tidal amplitude in the world.• Some concern about build-up of already worrisome amounts of industrial and agricultural waste, however, thermodynamic study showed this to be unfounded.• Highway has been proposed for area, and a tidal plant could serve as plant/road.• Already 50 million tons of dirt/waste that can be used for foundation less than 40 km (24 miles) from estuary.p. 277, Charlier1.011 Project Evaluation Spring Term 2003Libby Wayman, Michael Star, Ana Albir Page 2Current (1977) Severn Situation• Generally, tidal power has to prove cheaper than the amount of coal (cheapest) need to produce an equivalent amount of energy.• Also, in 1977, competing with nuclear and possibility of thermal (ocean) power.• Assuming a capacity of 5,000 MW (probably more), a tidal plant would generate in its lifetime (100 years) as much as all the oil suspected to be in the British North Sea.• Plant could produce 8,000-14,000 GW/hr, or about 5% of current British energy consumption.• Would produce about $2.2 million a day.Current Situation, continued• Be a constant, reliable source of energy for next 100 years (as opposed to oil, nuclear, etc. that have political ties and such).• Impact on ascetics of area would be minimal, as barrage would bring tidal amplitude to normal level for Britain.• Also, barrage holding back tides would also hamper soil erosion in area, and use of waste soil around area would reclaim agricultural land.p. 280, CharlierConclusions• Tidal power plant would bring economic development to Severn River region of Britain, as well as produce a stable source of energy for the entire country.• Economics of building such a plant seem to be quite expensive, and will need a professional analysis.• Environmental impacts should be investigated to a greater extent for consideration of project.Expected Profitability13.7 TW h3.9 p/KWh0.055 %/1000.055 %/100-0.429 p/KWh0.08 %/100184.2263 M PoundsFull-Scale Annual Energy OutputBase Price of Energy Operating Costs as a % of RevenueCost of Improvements as a % of RevenueOperating Cost (Improvements Incl.)Discount RatePresent Worth at year zeroCash Flows for Cardiff Weston Barrage-1200-1000-800-600-400-2000200400600800Proje ct Ye ar ( -5 to 95)Million PoundsCos tsRevenuesFuture Values After 95 Years of Operation-8000000-6000000-4000000-200000002000000400000060000008000000Million PoundsCos tsRevenuesEnvironmentDestroy this unique ecosystem?EnvironmentLarge Intertidal ZonesLarge tidal rangeHigh turbidityVarying salinityDistinct sedimentation patterns1.011 Project Evaluation Spring Term 2003Libby Wayman, Michael Star, Ana Albir Page 3EnvironmentRESTRICTPRODUCTIVITY!Environment• Fish Populations?– Threat to salmon young who require strong currentsÌLow head turbines not threatening to fish• Intertidal Zones?– Converted to subtidal zones– Reduce foodstock to birdsÌFoodstock NOT limiting to bird populationRevenue wrt Market• Revenue depends on firm power revenue and tariff revenue. – Firm power revenue = base revenue received regardless of amount of power consumed= Firm power rate x Firm power –Tariffdepends on total Market Supply and the Market Demand.What are the effects of inaccurate estimates of price and tariff on profitability? Revenue Parameters• FP revenue = FP rate x FP – FP rate determined by the CEGB– Allowed to grow with price of coal for 30 years, then capped at 40 pounds/KWh– Firm Power determined by CEGB = 1.1GWh•Tariff– Determined by Bulk Supply Tariff (BST) which is an effect of market supply and demand– Modeled by the Sizewell B. ProjectRevenue Sensitivity• Firm Power Revenue variation estimated up to 20%• Tariff variation estimated up to 50%Revenue Sensativity-2000-1500-1000-5000500100015002000250025% 75% 125% 175%% Variation from EstimatePW of PlantFPRevTariffCapital Costs• Few tidal power plants are in operation• Is there sufficient experience to accurately predict capital costs?• How much error can we expect in the estimates of capital costs?What will the effects of the error be?1.011 Project Evaluation Spring Term 2003Libby Wayman, Michael Star, Ana Albir Page 4Capital CostsMechanical Works•Turbines•Negligible VariationsElectrical Works•Transmission and Control•Up to 10% VariationsCivil Works•Only area of little experience •Barrage•Caisson•Up to 20% VariationsCapital Costs SensitivityCost Sensitivity02004006008001000120060% 70% 80% 90% 100% 110% 120% 130%% Va ria tion from Estima tePW of Plant (Million Pounds)Transmission


View Full Document

MIT 1 011 - SEVERN TIDAL POWER

Download SEVERN TIDAL POWER
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...
Login

Join to view SEVERN TIDAL POWER and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view SEVERN TIDAL POWER 2 2 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?