chambersburg - dhs

Chambersburg Renewable Energy Feasibility StudyWind Turbine

By Jinliang Li100 South 2nd Street

Tele: (717) 264-5151 Fax: (717) 261-3240

[email protected]://

www.borough.chambersburg.pa.us/electric.php

Project Director: Rick BlumProject Mentor: David SoystorSoyster

David, 11/22/15,

With this page being all text boxes, it is very difficult to edit.I do not think you need Chambersburg contact information on the version for the University.

Table of Contents[I.] Executive Summary..............................................................12

HighlightsObjectivesMission StatementKeys to Success

Sponsor Information Summary of Recommendation

[II.] Description of Technology..............14Wind Turbine TechnologyPennsylvania Wind MapWind Farm in Pennsylvania Recommended Wind Turbine Model Analysis

I.[III.] Marketing.....................................10Wind Turbine Market AnalysisPotential Suppliers InformationCompetition Matrix

IV. Site Plan & Construction Cost ………………………….………………………. 12

Construction LocationSite Plan

Installation Cost

V. Financial Analysis ………………………………………………………..…….. 15

Start-Up CapitalCash Flow

PAGE | 1

VI. Recommendations ……………………………………………………….……… 16

VII. Appendix ………………………………………………………………………… 17 Reference Page

PAGE | 2

Executive SummaryThis Project is a feasibility study of wind turbine that aims to illustrate the Chambersburg’s on-site future power generation plans on renewable energy. The project consists of five phases: the first phase is a study of wind turbine mechanism and its technology investigation, which could be reviewing a large amount of literature and scientific journals. The Second Phase is an analysis of the Chambersburg construction field, Pennsylvania wind map and case study of local existing wind farms requires customer contacts and field study. The Third phase is based on the wind map and Chambersburg’s filed size choosing the proper wind turbine components (turbine, convertor, blade, pole, construction base) including turbine model, pole height, unit numbers, and potential components suppliers. The present of the third phase would be a pro and cons table of various turbine models. The Fourth phase would be an energy output study of wind farm and its construction design strategy like construction array methods showing as a blue map for future construction plan. The last phase of this project would be project total cost estimation along with a possible payback period study, which would presents as cash flow charts or table lists. The financial estimation will include design expense, turbines purchasing price, construction fee, and wind turbine future maintenance consumption.

This project is a feasibility study for a wind farm for the Borough of Chambersburg. The Borough of Chambersburg has existing fossil fuel generators on site, but would like to expand their generation fleet by incorporating some renewable energy sources. Chambersburg is currently conducting a feasibility study for a photovoltaic solar array, and this study will complement that study.

The paper will provide an overview of wind turbines, discuss the proposed site location and expected wind speeds based on wind maps. The paper will then discusses the selection of the wind turbine, given the constraints of the project to maximize the electric generation potential. In addition, proposed site plan is developed, showing the location and arrangement of the wind turbines. Finally, a financial analysis is presented, showing construction cost, maintenance cost, and projected income.

PAGE | 3

soystedh, 11/22/15,

Look at these two paragraphs and see if that captures what you are trying to say in the Executive Summary.

soystedh, 11/22/15,

The five phases or sections should relate to your outline, but it does not.

soystedh, 11/22/15,

This is hard to read. Look at my two paragraphs below as an example of what an Executive Summary should look like.

Highlights

2013 2014 2015 2016 2017 2018 2019 2020 2021 2022290,000

300,000

310,000

320,000

330,000

340,000

350,000

360,000

370,000

380,000

390,000

Chambersburg Power Supply PortfolioM

Wh/

Yr

Figure1. Through 2013-2022 Chambersburg Power Supply Portfolio

ObjectivesThis Project is aim to develop a wind turbine feasibility study to illustrate Chambersburg on site future power generation plans on renewable energy.The Output of this project should include following aspects:

1. A Detail Feasibility Study of Wind Turbine in Chambersburg2. A Construction Strategy3. An Output study of the designed Wind Turbine4. Financial Estimation of Payback Period

The objective of this paper is to develop a feasibility study for the installation of a wind farm for the Borough of Chambersburg. The study will investigate and recommend a specific wind turbine model, propose a site layout, and summarize the financial aspects.

Mission StatementChambersburg is a unique smart-grid based self-sufficient electric utility in Pennsylvania. It is a real-world example of how a small utility can be successful. Chambersburg is famous for its low electric price rates and it is time to add another title of “Green Energy Generation”. In August3, 2015, Present President Obama and EPA has announced a new Clean Power Plan, which is requiring a dramatically reducing the Carbon pollution from power plants. So it is a great opportunity to introduce wind and solar energy into PAGE | 4

soystedh, 11/22/15,

Professor Blum noted this mistake on your poster. I would have expected you to be proactive and also make the change in your paper.

soystedh, 11/22/15,

I would be careful about using words like famous

soystedh, 11/22/15,

Look at my paragraph below and see if this sounds better

soystedh, 11/22/15,

This is more of background. A mission statement is typically associated with a group or company, not so much a paper.

soystedh, 11/22/15,

Does this paragraph concisely say the same thing?

soystedh, 11/22/15,

If you want to state the objective of the paper, you may want to put that second, after the background.

soystedh, 11/22/15,

This is not the supply portfolio. You used the portfolio data to make basically a projected annual electric need

soystedh, 11/22/15,

You typically do not start a section with a figure. I do not see where you even reference it.

soystedh, 11/22/15,

I do not see anything written as a highlight. I would think you would want to start your paper with a background section.

Chambersburg power file sector, which could not only resolve the carbon emission regulation issues but also can expand Chambersburg’s electric generation profile.

The Borough of Chambersburg is a unique small municipal electric utility in Pennsylvania. The unique characteristic is that Chambersburg has the ability to buy power from the Regional Transmission Operator (PJM) or completely disconnect and use their own generators to meet the electric needs. This flexibility allows them to make supply decisions which in turn will lead to lower electric rates for their customers. In addition, with having their own generation fleet, Chambersburg has a redundant supply, which leads to high reliability.

With the emphasis on renewable energy and reducing carbon footprint, Chambersburg would like to investigate the possibility of installing a wind farm. There are several objectives of the wind farm. The most obvious objective will be to generate electricity from a renewable energy source. However, it will also serve as a teaching opportunity and positive public relations. The Borough of Chambersburg projects that their electric demand will continue to increase through 2022, see Figure 1. To meet this growing demand, Chambersburg needs to expand their generation fleet, and they want to consider renewable energy as part of the solution.

Keys to Success1. Wind Turbine Technology Investigation 2. Wind Turbine Model Decided3. Wind Turbine Main Components Chosen4. Approval of Wind Turbine Output5. Construction Strategy and Trade-off Analysis6. Total Cost Estimation7. Pay Back Period Approximation 8. Poster Design and Final Presentation to Industry9. Project Report Hand-In on December 4th

Sponsor Information Chambersburg is a unique self-sufficient power utility in Pennsylvania. It owns and operate its own generation, transmission, and distribution power system. They have the lowest electric rate in Pennsylvania with an excellent reliability record — two hours outage per year. Chambersburg own two electric power plants with total 30 MW per year power generation. If any additional electric is required, the Borough of Chambersburg also has the ability to take power from PJM grid to fulfill the customer needs. The Chambersburg PAGE | 5

soystedh, 11/22/15,

Make sure that is a true fact. You could say one of the lowest if you are not sure.

soystedh, 11/22/15,

You can really take some of this and re-word it into the background. I touched on some of this in my paragraph.

soystedh, 11/22/15,

How does this fit into your paper?

Electric using character, competence, and collaboration provide to their customers valuable energy products and services that are safe, reliable, and competitively priced. Chambersburg is a great example of a small self-sufficient utility can function and be successful.

Summary of Recommendations• Financially, the project cannot be justified due to the long payback period of time

which is about 40 years. It will greatly exceed the wind turbine designed life which is 20 years.

• The wind turbine may provide other benefits to Chambersburg such as improved public image through green generation and being a new technology adaptor.

Description of TechnologyWind Turbine TechnologyA Wind Turbine is a device that capturing natural air flow’s kinetic energy converts into electric power. When air go through the blades, which spins along with the shaft. The shaft is connected with a generator and makes electricity. Due to the characteristics of wind power generation, it is essential for engineers’ design concerns that the turbine would be exposed to strong wind environment. So an Aerodynamic model of the wind turbine usually would be used to maximize the wind turbine’s efficiency by determine the optimum tower height, reliable control systems, number of blades and blade shape. Most wind turbine are consisted with three main components, generator, rotor, and support structure. Today's wind turbines are manufactured in a wide range of both vertical and horizontal axis types. The smallest turbines may used for applications like battery charging or to power traffic warning signs. Medium size turbines can be used for making contributions to a domestic power supply while selling unused power back to the utility supplier via the electrical grid. Arrays of large turbines, known as wind farms/ wind power generation station, are becoming an increasingly important source of renewable energy and are used by many countries as part of a strategy to reduce their reliance on fossil fuels.

PAGE | 6

David, 11/22/15,

I understand what you are saying, but the paragraph is hard to read – it does not flow. It looks like you wrote some, copied some, or tried to change a few words from something that you copied.Each paragraph in your paper should have a single point – this paragraph jumps around with multiple points.You have several fragments in this paragraph.You included Figures 3 and 4, but never refer to them. You could have several paragraphs for this section. You can refer to the figures and explain the main components.

soystedh, 11/22/15,

For a paper, I would not use two bullet points for a section. I would just use paragraphs.

PAGE | 7

Figure 2. The main components of a wind turbine

Figure 3. The power generation layout of wind turbines

Pennsylvania Wind Map

From the Pennsylvania wind map (Figure 4) we can see the location of Chambersburg is besides the town of York and the annual average wind speed at 80m in Chambersburg is around 7 m/s. 7 m/s is a relative low wind speed for construction of wind turbine farm. Comparing with other places in Pennsylvania such as Sandy Ridge, Allegheny Ridge, and Mill Run, which have a higher wind speed around 10 m/s, Chambersburg may require special designed low wind speed wind turbine for an efficient energy output.

PAGE | 8

Figure 4. The Pennsylvania – Annual Average Wind Speed map in a height of 80 m

David, 11/22/15,

I think you are trying to say something like “The wind speed range for a typical wind farm is typically around 9 to 10 m/s. With Chambersburg being below this, a turbine that is designed for lower wind speed will need to be used” or something like that.

Wind Farm in Pennsylvania

The Bear Creek Wind Power Project, Pennsylvania's newest wind farm, is a 24 MW wind energy facility located in the Pocono Mountain region of Pennsylvania less than 10 miles southeast of Wilkes-Barre in the town of Bear Creek. Visible while heading south on the Pennsylvania Turnpike's Northeast Extension, the Project is expected to produce over 75 million kilowatt-hours of wind energy annually.

The Green Mountain Wind Energy Center, located in Somerset County, is situated on land reclaimed from a coal strip mine. It includes eight 1.3 MW turbines for a total output of 10.4 MW - enough to power 3,300 homes.

PAGE | 9

Figure 5. Bear Creek Wind Power Project, Bear Creek, PA

Bear Creek

Owner/Operator: Wind Park Bear Creek LLC

Output: 24 MW

No. of Turbines: 12 (Gamesa 2.0 MW)

Operational Since: February, 2006

Green Mountain

Owner/Operator: FPL Energy

Output:64.5 MW

No. of Turbines: 43 (GE 1.5 MW)

Operational Since: October 2003

Figure 6. Green Mountain Wind Energy Center, Garrett, PA

David, 11/22/15,

This section shows two examples of wind farms, but how does it tie into your paper? What point are you trying to make? Are you showing two sites at high wind areas? You need to develop and expand this section. You may need to look into these turbines – what is the height, blade length, wind speed operating range, etc. Are you trying to show that each site requires a different solution?

Recommended Wind Turbine Model AnalysisHigh Output Wind Turbine for Low Wind Regimes – NPS 60-24

Reasons for Choosing NPS 60-24 Model for Chambersburg

Low wind speed design The Turbine is designed for specific low wind speed (10 m/s), which is suit to Chambersburg low wind speed region.

Easy to construction The Turbine’s hub is designed in 23 meters, which is relatively convenient to install and suit to the construction landscape.

Plug and Play The Turbine is design to simplify grid interconnect, because the construction ground is located besides a transmission station, it is essential to consider that the simplicity of plug and cut-off the wind turbine system.

Quiet The gearless design, advanced blades, and low rpm and tip speed, all contribute to low noise levels. Considering the residential in Chambersburg, Quietness is a unique benefit to Borough of Chambersburg, which may bring positive public image.

Easier Permitting The lower hub height helps Chambersburg to permit on site wind power generation proposal.

PAGE | 10

Figure 7. NPS 60-24 on site photography

David, 11/22/15,

Good point, go ahead and state how high the pole will be.

David, 11/22/15,

Quiet is a good aspect. Go ahead and expand on this. What is the tip speed of this design vs. the other two examples? What are the trade-offs of a gearless design?

David, 11/22/15,

I honestly am not sure what you mean here. I don’t know if you mean that the site that Chambersburg selected is near a substation, and if so, how does that impact the model recommendation?

David, 11/22/15,

Not sure what that means.

David, 11/22/15,

I see Table 1 below, but I do not see where you refer to it.

David, 11/22/15,

Typically, a formal paper has more explanation than just several bullet points.

David, 11/22/15,

Consider expanding this section to describe the step you performed to make your recommendation. In other words, what are the constraints that are different from the two examples you gave earlier?

Specification of NPS 60-24 Table 1, Specifications of NPS 60-24 from Northern Power System Crop. General ConfigurationDesign Life 20 yearsRotor Diameter 20 meterTower Type Tubular steel monopoleHub Height 23mOrientation Upwind, 3 bladesPower Regulation Variable speed, stall controlCertification CE compliant CEI 0-21PerformanceRated Wind Speed 7-10 m/sCut-in Wind Speed 3m/sCut-out Wind Speed 25 m/sExtreme Wind Speed 45m/sWeightRotor & Nacelle 6800 kgTower 10,000 kgDrive TrainGear Box Type No gearbox (direct drive)Generator Type Permanent magnetBraking SystemRedundant Braking Generator dynamic brake and multipleSystem Hydraulic calipersControl SystemController Type DSP-based multiprocessor embedded platformConverter Type Pulse-width modulated IGBT frequency converterMonitoring System SmartView remote monitoring system, ModBus

TCPElectrical SystemRated Electrical Power 59.9 kw, 3 Phase, 400 VAC, 60 HzPower Factor Set point adjustable between 0.9 lagging and

leadingReactive Power +/- 30 KVARGrid Interconnect Utility approved protective relay includedNoiseApparent Noise Level 55 dBEnvironmental SpecificationsTemperature Range Operational -15 °C to 40 °CTemperature Range Storage -25 °C to 50°CLighting Protection Receptors in blades, nacelle lighting rod and

electrical surge protection

Turbine Maintenance Guarantee from Manufacturer

10-Year Performance Guarantee Program (PGP) The 10-Year PGP covers 10 years of operation and maintenance costs, including parts, labor and expenses for the NPS 60. The annual cost is based on the performance of the NPS 60. This is backed by an availability guarantee and performance to power curve guarantee. During the programmer NPS will be the sole service provider. This gives peace of mind that the wind turbine will produce maximum energy and return on investment while offering the lowest

PAGE | 11

total cost of ownership for the turbine’s 20+ year life. With the 10-Year Performance Guarantee Program, Northern Power Systems is financially invested in the success of your wind turbine.

Power Curves

MarketingMarket AnalysisSince 1981, the great dropping in gasoline price, the price of wind power electricity in United States has also decreased from about 25 cents/ kWh to averaging near 4 cents/ kWh in 2008. Even though wind turbine prices is continually increasing since 2005, in area with the high wind speed, wind power is cost completive with new generation from coal and

PAGE | 12

Figure 8. NPS 60-24 power curve in various hub height

Figure 9. NPS 60-24 power curve in various wind speed

David, 11/22/15,

You may want to state where you found that

David, 11/22/15,

How does gasoline play into your paper? Gasoline is low now, but it was not several years ago

David, 11/22/15,

Look at the graph and your title – they need to match. The title should be something like Annual Energy Output vs. Average Annual Wind Speed

David, 11/22/15,

Text boxes are hard to edit. Think the title for Figure 8 should be something like power output vs. wind speed, not hub height.

natural gas plants. With the development of the new technology in wind turbines, the wind power costs become more and more competitive, demand is exponentially growing all over the world.

Global wind power capacity increased from about only 6,000 NW in 1996 to more than 282,500 MW by the end of 2013. The growing of wind power generation has been a trend that would not stop in the market of Canada, United States, China, India, and Europe.

At the End of 2013, the United States wind power market has reached more than 60,000 MW, which nearly half of the capacity in Texas, California, Iowa, Illinois and Oregon.

Recommended Turbine Model Supplier InformationNorthern Power Systems has been delivering innovative energy solutions in a changing landscape for over 40 years. Around the globe, our installed base of Permanent Magnet Direct Drive “PM/DD” wind turbines and grid-friendly power technology components have logged millions of kilowatt-hours of operation to date, demonstrating our commitment to performance and reliability. Northern Power Systems offers comprehensive in-house development services, including systems level engineering, advanced drivetrains, power electronics, Permanent Magnet machine design, and remote monitoring systems to the energy industry. Northern Power Systems is headquartered in Vermont, USA with operations in Massachusetts, USA, as well as Switzerland, the United Kingdom and Italy.PAGE | 13

Figure 10. Wind power growth in the world electrical market

David, 11/22/15,

This whole paragraph looks copied. The word “our” gives it away.

David, 11/22/15,

This is another figure that you do not reference. What point are you trying to make? The paper is for Chambersburg, but you have data from all over the world. That is OK, but state what you are trying to say.

David, 11/22/15,

Do you mean continue to grow?

David, 11/22/15,

Give reference

David, 11/22/15,

Do you mean MW?

Turbine Price

Market Percentage

Transmission Station

Company Address: Northern Power Systems, 29 Pitman Road, Barre Vermont, 05641, USAPhone: 802-461-2903Email: [email protected]

Competition Matrix

Site Plan & Construction CostConstruction Location

PAGE | 14

Figure 11. Wind power generation market competition matrix in U.S.

David, 11/22/15,

This section has no writing – just a figure. Again, what is the point you want to make?

Construction Site Plan

For the safety reasons, it is important to save have proper safe distance from the boundary of the construction land.

Installation Cost The installation costs includes the expenses required to construct and set the turbine up as long as requiring associated facilities. The construction scheme requires to hire experienced contractor to prepare the site, install the turbines, and connect the turbine along with the converter into grid system. During the construction progress, Chambersburg will corporate with the construction contractor, representatives from the turbine manufacturer, and engineers from PJM transmission. The construction project of wind turbine could be divided into five majority cost includes: control center, tower foundations, wiring to the tower bases, and turbine erection and security fences.

Control room: a reliable control room is the key to make right decisions on distribution operations and emergency situation control. In order to attain the highest level of operational efficiency on wind turbine, the control room must contain three basic functions:

1. Track and RestorePower outage restoration planning, dispatching.

2. Operate and MonitoringTurbine control, switch planning, networking management

3. Analyze and optimize

PAGE | 15

Figure 12. Construction location present in Google Map and analysis

Figure 13. Construction Site plan and area calculation

David, 11/22/15,

Since Chambersburg has a control room, then just state that. The modification, I think, is just a SCADA addition. You need to define SCADA first (Supervisory Control And Data Acquisition)

David, 11/22/15,

Do you mean cooperate?

David, 11/22/15,

I basically know what you are trying to say, but it needs a lot of work.

David, 11/22/15,

For construction point, do you mean tower location?

David, 11/22/15,

The set-back for construction is more of a permit issue than safety. In the US, we typically give distances in feet.What is the arrow for?

Engineering analysis, grid optimization

Since Chambersburg already have a control room the add-in wind turbine control may cost range of $10,000-15,000.

Tower foundation: this cost highly depends on the height of tower and weight of the generator assembly and rotor, plus the soil conditions at construction site. Based on our current research, the height of tower is 20 meters, the total weight of generator and rotor is about 6800 kg, the soil condition under the construction site is unknown, so the estimation cost of this section may range from $ 60,000 to $ 100,000.

Wiring to turbine base: this cost includes installation of a pad mount transformer at the turbine base if required, underground wiring on the property, electric poles to carry the power to the utility line if required, and installation of all these components. The cost range is $8,000 to $20,000. Due to the construction location is right beside a transmission station, the wiring distance is reduced to a minimum level.

Turbine erection: The major cost in the erection process is the rental of a crane. A 300-foot crane with the necessary 400- plus ton capacity can cost $80,000 or more for a single day. Considering weather delays or other difficulties, the rental charge of the crane might add 10% per day to construction costs. A comprehensive price estimate from a qualified installation company will likely be in the range of $80,000 to $120,000 per MW.

Security fences: For security reason, the fences should build along the landscape boundary to prevent residential enter without awarenessunauthorized access. According to Figure 13, the total length of fence inned is X feet. tThe current price of iron fences is about $15/feet, so the estimation cost of the security fence ranges from $6500 to $ 10,000.

PAGE | 16

David, 11/22/15,

Do you need man gates or gates for vehicles? Where they included? What about security lighting?

David, 11/22/15,

Why are you giving cost per MW? You know the total nameplate installation amount.

David, 11/22/15,

A 400 ton capacity crane? That is 800,000 pounds! Above, you said the rotor weight was 6800 kg, which is 15,000 pounds

David, 11/22/15,

Table 1 shows an output of 400 VAC. Does the existing substation have that voltage? If not, an intermediate transformer will need to be installed, which is an additional cost.

David, 11/22/15,

You can state that a geotechnical report should be performed to properly design the foundations.

Financial Analysis Start-Up Capital

Cash Flow

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30-$20,000

$0

$20,000

$40,000

$60,000

$80,000

$100,000

$120,000

$140,000

$160,000

$180,00030-Year Dollar Cash Flow

Cash-Flow

PAGE | 17

Figure 14. Approximation of Start-Up Capital and Future Potential Cost

The Start-Up Capital here refers to the money that is required to begin the project, which includes the cost of design, permits, licenses, construction, and future maintenances.

Figure 15. Approximation of 30-year dollar cash flow chart

Cash Flow

(Revenue –

Expense)

Investment Year

David, 11/22/15,

Interesting figure, but what conclusion do you want the reader to get?

Recommendations Based on financial considerations alone, the payback period is longer than the expected life of the assets. Therefore, a wind turbine demonstration does not make financial sense.

However, there are other benefits to a wind turbine demonstration such as public image, green generation, etc. That that may benefit the Borough of Chambersburg. These other benefits may outweigh the potential financial loss. The final decision on the wind turbine demonstration will be made by the Borough of Chambersburg.

PAGE | 18

David, 11/22/15,

Add a sentence stating the payback period and the expected life.

Appendix Reference PageTweed, K. (n.d.). Wind Turbines Power Liquid-Air Energy Storage. Retrieved September 18, 2015.

Garvey, S. (n.d.). An Energy-Storing Wind Turbine Would Provide Power 24/7. Retrieved September 18, 2015.

Levitan, D. (n.d.). Supercomputing a Quieter Wind Turbine. Retrieved September 18, 2015.

Doman, G. (2009). Structural Dynamic Considerations in Wind Turbine Design. Wind Turbine Technology: Fundamental Concepts in Wind Turbine Engineering, Second Edition, 585-604.

Dual Purpose Design of Small Wind Turbine Blades. (1989). Wind Engineering,12(1232332), 511-527.

Matsumiya, H. (n.d.). New small turbine technologies. Wind Power Generation and Wind Turbine Design WIT Transactions on State of the Art in Science and Engineering, 389-413.

Tong, W. (n.d.). Fundamentals of wind energy. Wind Power Generation and Wind Turbine Design WIT Transactions on State of the Art in Science and Engineering, 3-48.

Jamieson, P., & Hassan, G. (2011). Innovation in wind turbine design. Hoboken, N.J.: Wiley.

Eggleston, D., & Stoddard, F. (1987). Wind turbine engineering design. New York: Van Nostrand Reinhold.

Fox, C. (2013, May 1). Reinventing the Wind Turbine: Steve Apelman's Design Finds Itself on the Cusp of Overshadowing Existing Tech with a Simple Approach. Product Design & Development.

Carvallo, A., & Cooper, J. (2011). The advanced smart grid edge power driving sustainability. Boston: Artech House.

Gellings, C. (2009). The smart grid enabling energy efficiency and demand response. Lilburn, GA: Fairmont Press.

Clean Energy Deployment Administration: Hearing before the Committee on Energy and Natural Resources, United States Senate, One Hundred Twelfth Congress, first session, to receive testimony on the proposal for a Clean Energy Deployment Administration, as. (2011). Washington: U.S. G.P.O.PAGE | 19

David, 11/22/15,

I think you need to have reference numbers in your paper for the various sources, specifically for certain statistics.

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