Tri-Town_ORR_Preliminary_Site_Analysis

noturbine

Tri-Town_ORR_Preliminary_Site_Analysis

Wind Power in Mattapoisett, Marion & Rochester:

Siting Considerations for a Met Tower

and Fatal Flaws Analysis for a Wind Turbine

This report was funded by the Massachusetts Renewable Energy Trust’s Community Wind

Collaborative on behalf of the towns of Mattapoisett, Marion & Rochester. It was prepared by Sally

Wright and Lynn Di Tullio of the Renewable Energy Research Laboratory at the University of

Massachusetts.

Table of contents

1. Introduction

2. Sites Considered

3. Predicted Wind Resource

4. Wind Turbine Siting Considerations and Fatal Flaws analysis

5. Anemometry Siting Considerations

6. Anemometry Installation Logistics

7. Conclusion & Next Steps

Locator Map

X

Mattapoisett


1. Introduction

At the request of the Massachusetts Technology Collaborative’s Renewable Energy Trust, Sally Wright

and Lynn Di Tullio of the UMass Renewable Energy Research Laboratory (RERL) visited potential

wind turbine and/or wind monitoring sites in Mattapoisett, Marion, and Rochester, along with

representatives of the towns. This report focuses on the siting considerations for wind-monitoring towers

(“met towers”) as well as some of the logistics for met tower installation. Additionally, it takes into

consideration logistical considerations in a broad “fatal flaw” analysis for potential wind turbine

installations. This report is not intended as and should not be considered a wind turbine siting study.

Section 2 begins by describing the sites that are under consideration for a met tower and/or wind turbine,

and subsequent sections look for positive and negative indicators of their suitability.

Section 3 describes the predicted wind resources for these sites. If a site weren’t expected to have good

wind, it would not be considered further.

Section 4 then looks for fatal flaws for wind turbines at the sites.

Sections 5 and 6 look at the possibility of installing a met tower at these sites.

Section 7 summarizes major concerns and suggests next steps.

For more background information

This document assumes some familiarity with wind resource assessment, wind power siting, and other

issues that arise with wind power technology on a community scale. For an introduction to these areas,

please refer to RERL’s Community Wind Fact Sheets, which are available on the web at:

http://www.ceere.org/rerl/about_wind/. These sheets include information on the following subjects:

• Wind Technology Today

• Performance, Integration, & Economics

• Capacity Factor, Intermittency, and what happens when the wind doesn't blow?

• Impacts & Issues

• Siting in Communities

• Resource Assessment

• Interpreting Your Wind Resource Data

• Permitting in Your Community

Use of this report

This engineering report is intended to be used in consultation with MTC as the town explores its options

for participation in MTC’s Community Wind Collaborative.


2. Sites considered

Town representatives suggested eight locations for consideration. They are listed in the table below.

Several sites were eliminated from consideration for a met tower for technical reasons: lack of access,

proximity to residences, or firm ground.

# Site Notes Consider further?

1 Brandt Island Road Town Land Flat, forested land on Buzzard’s Bay Yes

2 Old Rochester Regional (ORR)

High School, Marion &

Rochester

3 Marion Wastewater Treatment

Plant

Flat, forested land off playing fields Yes

Inland, lower predicted wind speeds Yes

4 Mattapoisett Neck Rd. Marshy; residential area No

5 Ned’s Point Close to a residence No

6 Angelica Point No road access to end of point;

unsuitable for standard anchors

7 Strawberry Point No road access No

8 Mattapoisett Landfill Inland – insufficient winds, unstable

base

The town-owned land on Brandt Island Road and Mattapoisett landfill sites were not toured on this site

visit.

Only three sites will be considered further in this report:

A. Town Land off Brandt Island Road

B. Old Rochester Regional (ORR) High School

C. Marion WWTP

Note that turbines and met towers have different siting requirements; ruling a site out for a met tower

does not necessarily rule it out for a wind turbine.

Following is a listing of site characteristics for these three locations. Also included are maps and

photographs for the sites.

No

No


Site characteristics

Site: A. Brandt Island

Road Town Land

Description Mostly undeveloped,

forested town-owned

land near the coast of

Buzzards Bay.

Address Mattapoisett, MA

02066

B. High School C. WWTP

Flat forested land off

playing fields

135 Marion Road,

Mattapoisett, MA 02066

Owner Town of Mattapoisett Tri Towns: Marion,

Mattapoisett & Rochester

Location (NAD 27 UTM

19)

Location (NAD 83, D-M-S) 41° 37' 51"N, 70° 49'

59"W

Wastewater Treatment

plant. Proposed met tower

site is currently used for

storage of DPW materials

50 Benson Brook Road

Marion, MA 02738

Town of Marion

347258E 4610196N 351570E 4615205N 352106E 4618098N

41° 40' 36"N, 70° 46'

57.5"W

GPS Point No.: None 237 238

Power lines or other

obstructions to met tower.

(Met tower must be set at least 1.5

x the tower height away from

power lines.)

Clearing, terrain, obstacles

to wind

Road Access -for met tower

installation

Soil quality-for met tower

anchors

Ok Ok Ok

50-60’ trees.

Will require clearing

None seen, but not far

from the road.

50-60’ trees

Will require clearing

Good Good

OK OK OK

Security: Unknown Possibility of vandalism

related to high school.

Distance to Distribution/

Transmission lines

OK OK OK

41° 42' 10.2"N, 70° 46'

36.9"W

Some trees and other

debris.

Will require clearing

Locked Gate - could

prevent vehicle access at

night

On-site electrical loads None OK Good - WWTP

Public or military airports

within 5 miles

Nearby residential areas: Houses at most 650 feet

away, depending on

siting

None None None

Houses 2040+ feet to east House 1300 feet to east


Maps:

Base map source: Ortho-photograph from MassGIS website, http://www.mass.gov/mgis/dwn-imgs.htm

Brand Island Rd.

Map

1: Ortho-photograph of the Brandt Island Road area. One possible turbine location, away from

Brandt Beach Avenue residences, is marked with an X


Map 2: Orthophotograph of the high school area, with the proposed met tower location marked with an

X


Map 3: Orthophotograph of the wastewater treatment plant


Map 4: Portion of an Assessors Plan of the Town of Mattapoisett, showing the town-owned parcel

number 6, to the east of Brandt Island Road, with frontage on Brandt Island Road


Map 4: Estimated annual average wind speed at a height of 70 meters

Approximate locations under discussion are marked with yellow crosses.

Sites

of primary interest for wind power have a mean wind speed of 6.5 m/s or over, i.e. shown in dark

green, pink or orange.

For more information, see TrueWind Solutions, truewind.teamcamelot.com/ne/.


Photos

View of site just off playing field at ORR High School, looking approximately north:

Above left: view of site near wastewater treatment plant, looking south.

Above right: view of wastewater treatment

plant area, looking about west.

No photographs were taken of the Brandt Island Road town parcel.


3. Predicted

Wind Resource

TrueWind estimates of annual average wind speed

According to the modeled wind speeds in the TrueWind map included on the first section of this report,

predicted annual average wind speeds are as follows:

Estimated

annual average

wind speeds

At a height of

70 m

A. Brandt Island Road

Town Land

B. High School C. WWTP

6.7 m/s (14.9 mph) 6.4 m/s (14.3 mph) 6.1 m/s (13.7 mph)

These TrueWind estimates are used for screening and do not eliminate the need for site-specific

anemometry.

The importance of wind speed

The feasibility of wind power depends on many factors. One of the most important factors is wind

speed. The power in wind is related to its speed, and small changes or inaccuracies in wind speed can

mean big changes in annual energy production. The chart below demonstrates the impact of mean wind

speed on wind turbine output at the sites under consideration. Note that both axes of this graph, wind

speeds and the annual energy, are estimates.


Other available wind data

RERL has not maintained any anemometry

in this immediate area. The nearest RERL anemometers are:

Falmouth (~10 miles), Dartmouth (~12 miles), and Bourne

(~12 miles). Data from these anemometers

are available at: http://www.ceere.org/rerl/rerl_resourcedata.htm l.

Obstacles to wind flow

Obstacles

cause both turbulence and slowing of the wind. These are important factors in site selection

for a wind turbine because they affect the power production and the longevity of a wind turbine.

A. Brandt Island Road

Town Land

B. ORR High School C. WWTP

Obstacles to wind Wooded, 50-60’ tall trees Wooded, 50-60’ tall. The Brush, 40-50’ tall trees;

flow: high school and

surrounding trees will

cause some turbulence.

WWTP building.

The land surrounding all three sites is largely wooded or built-up; this roughness increases turbulence.

Proximity of anemometry & turbine

Note that while wind resource assessment directly on the proposed wind turbine site is preferred, it is not

always possible. If wind data are gathered in one spot, but a site for a wind turbine is later chosen in

another nearby location, then a computer model

that considers the wind data and terrain can be used to

extrapolate the data from one location to the other. However, as the two sites become farther apart, the

level of certainty in the data goes down, and thus the amount of risk in the investment goes up. It is

difficult to predict the rate at which the certainty changes with distance, and can only be estimated on a

site-specific basis.

Although the sites under consideration are in similar landscapes, they are over a mile away from each

other. Measurement at one site would not confidently be used to evaluate the feasibility of a turbine at

the other.

Conclusion: Appropriateness of resource assessment

The Tri-town area encompassing Mattapoisett, Marion, and Rochester has estimated wind speeds near

the shoreline that would be acceptable for the use in a megawatt-scale wind project.

If the towns have interest in pursuing a wind energy project, wind resource assessment is recommended.

The remainder of this report will look at preliminary siting logistics for wind turbines and met towers at

and around these sites.


4. Wind Turbine Siting Considerations

Purpose of this section

As mentioned in the previous section, it is important to try to measure the wind as close to a potential

wind turbine site as possible.

Therefore turbine-siting criteria should be taken into consideration when

siting a wind resource monitoring. The purpose of this section is to consider whether there are any “fatal

flaws” to siting a wind turbine in the general areas under discussion.

We

stress that a site for a wind turbine has not yet been considered in any depth and siting of a wind

turbine

is not the intended purpose of this report. Rather, this section is intended to inform the decision

of where to measure the

wind.

Furthermore, a scale of wind turbine has not been chosen. For the purposes of this discussion, it is

assumed that a commercial-scale (660 – 1,800 k W) wind turbine will be chosen.

Transportation accessibility for turbine installation

With blades up to 130 feet long, modern wind turbines require transportation on roads with a fairly large

turning radius and only small changes in slope.

Some of the roads leading to the Brandt Island Road parcel in particular are narrow residential roads.

Careful route planning will be necessary. However, site access does not appear to be a fatal flaw for any

of the sites.

In-site access issues

Note that the Brandt Island Road parcel only has road frontage on the far northern edge. If no access

were possible across private property on the western boundary (example shown below in blue), an

access road of about 1600 feet would need to be built in from the north (example shown in pink).

X

Example

of possible

turbine site


Distance to distribution or transmission lines for power distribution:

Distribution lines come on-site

at the school and at the WWTP. Distribution lines are further away from

the Town Land met tower location. A point of interconnection would be determined later in the project.

Noise

Noise considerations generally take two forms, state regulatory compliance and nuisance levels at

nearby residences:

A. Regulatory compliance: Massachusetts state regulations do not allow a rise of 10 dB or

greater above background

levels at a property boundary (Massachusetts Air Pollution Control

Regulations, Regulation 310 CMR 7.10). This sound level is very unlikely to be a reached in any

case at the sites we examined.

B. Human annoyance: Aside from Massachusetts regulations,

residences must also be taken into

consideration. Any eventual turbine would be sited such that it would be inaudible or minimally

audible at the nearest residences. At this stage, to check for “fatal flaws,” a rule of thumb can be

used: to minimize possible noise impacts, site wind turbines at least three times the blade tip

height from residences. Distances from mixed-use areas may be somewhat shorter.

Noise will not be an issue for siting a wind turbine at the ORR High School or the Marion WWTP.

However, noise

will be a primary siting constraint for the Brandt Island Road site because much of the

parcel is less than 800 feet

wide, and there are residences to the western side of the parcel. Consideration

of the neighbors will be an important factor in siting a wind turbine on this parcel of town land. Given a

specific size and make of turbine, suggested setbacks from residences can be proposed to eliminate or

minimize the audibility at the neighbors. This would then inform the exact siting of a turbine.

For example, a Vestas V47 on a 50-meter tower has a 241-foot blade-tip, and would need to be sited

on

the far eastern side of the parcel, to be three times the blade-tip height (723 feet) from the neighbors on

the western edge.

Nearby Airports

There are no public or military airports within 5 miles, so airspace will not be an important siting issue.

The nearest airports are:

• New Bedford Regional Airport: ~6 miles

• Acushnet River Seaplane Base, Fairhaven, ~4 miles

• Island Air Service Seaplane Base, Rochester, ~7 miles

• Otis Air National Guard Base, ~12 miles

The FAA requires that any structure over 200’ be lit. Any com mercial-scale turbine will be lit.

A Form 7460-1 (Notice Of Proposed Construction Or Alteration) must be sent

to the FAA for any

proposed wind turbine installation over 200 feet (to blade-tip). Any concerns of airport personnel and

other air safety regulators would be considered as part of the turbine siting process.


Other

environmental or permitting issues

The following items are favorable for this site:

Notes:

Item to check:

A. Brandt

Island Road

Town Land

B. ORR High

School

Designated by the DEP as Wetlands? No Some wetlands in

this area but they

can be avoided

Designated by the Natural Heritage &

Endangered Species Program as a:

• Core Habitat

• Priority Habitat of Rare Species, or

• Certified Vernal Pool?

No

No

Designated by the Massachusetts

Audubon Society as an Important Bird

Area (IBA)?

For more on Core Habitat C1297 in Marion, see:

http://www.mass.gov/dfwele/dfw/nhesp/twnrpts/marion_core_habitats.pdf

No

No

C. WWTP

No

Core Habitat

(see below)

There are two Mass Audubon IBA’s in the Buzzard’s Bay region: Bird Island and Ram Island, located

just offshore the western shoreline of Buzzards Bay.

The Marion Waste Water Treatment plant is in Core Habitat C1297 as designated by the Natural

Heritage & Endangered Species Program. The Core Habitat includes most of this area between Route 6

and Route 195.

Conclusion: At this preliminary

stage, there is no indication of significant environmentally based

permitting hurdles

for these sites.

No


Conclusion: Wind turbine siting

No fatal flaws to siting a wind turbine in the Tri-town

area are apparent. However, at the Brandt Island

Road Town parcel, constrained space would limit the number, size and siting of tur bines.

The two inland sites are expected

to have lower wind speeds, making

the Brandt Island Road area more

favorable. A comparison of important characteristics that affect project feasibility is summarized here:

Factor Site Brandt Island

characteristic Road Town

Land

High School WWTP

Wind speed: Predicted wind Good

Lower than

resource

typically desired

for the Community

Wind Collaborative

Number

of

turbines:

Available space Constrained

in size

& location


probably space for

only one turbine,

no bigger than

Hull’s V47

Value of power On-site None OK

produced electrical loads

Interconnection Distance to Ok

cost Transmission

/distribution

lines

Conclusion: influence on siting of wind resource monitoring

Sufficient Sufficient

Ok Ok

Lower

than

typically desired

for the Community

Wind Collaborative

Good – WWTP

Since the sites are not close enough together to share monitoring, a decision should be made on a turbine

site before choosing a met tower site. In other words, the met tower should be installed at the preferred

turbine site.


5. Choice of site for wind monitoring

Traditionally, wind is monitored for about a year with a met tower. Some sites may be suitable

for other

types of monitoring in addition to or even instead of a met tower. This section will concentrate on the

siting of a met tower, but will also discuss other monitoring options.

About

met towers

The met towers used by RERL

are temporary structures that

do

not

require a foundation and are supported

by

guy wires in 4

directions. Towers are usually 40 meters (131’) or 50 meters

(164’) tall. In most cases, standard utility anchors are used to

anchor the guy wires. The number and type of anchors required

depends on the particular site. They will be proof-tested at

installation to make sure they can hold enough load.

The tower is raised using a winch; no crane is required. It consists of a set of 6” diameter pipes that stack together; the whole set-up

can be brought in on a pick-up truck.

The pictures on this page give an idea of what this equipment

looks like.

Gin

Pole

Met

Tower

A met tower in the process of being raised.

The “gin pole” gives the winch leverage to lift

the tower.

RERL’s truck loaded with the sections of a 50-meter

met tower

A met tower base-plate

Typical 6-foot-long utility anchor

An anchor, installed, with 2 guy

wires attached


Space required for a met tower in general

Clearing is necessary both for met tower installation

and to reduce ground effect disturbance during data

collection. The cleared area is shaped like a circle for the guy wires, with an additional “wedge” in

which the tower is assembled before raising. The minimum cleared areas for guyed towers are:

Tower Height Minimum D Minimum L Total Envelope

(Guy Diam.)

(Space to lay the

tower down)

40 meter (131’) 160 feet 135 feet 215 x 160 feet

50 meter (164’) 240 feet 165 feet 285 x 240 feet

Dimensions of a football field, for comparison: 300 x 160 feet

In general, a larger cleared area reduces the disturbances seen by the instruments,

and improves data quality. Therefore, a cleared area larger than the minimum size

is preferred.

While it is not necessary to pull stumps, removing as much obstruction

and underbrush as possible will

facilitate the raising of the tower. Guy- wires will be pulled across this field, and any obstacles that

entangle the wires make the job more difficult.

It is also essential that there not be any electric or telephone wires within 1.5 times

the height of the

tower,

i.e. 200 feet of a 40 m tower, or 250 feet of a 50 m tower.

Trees must be cleared at least the height of the trees away from the anchors to eliminate the danger of a

fa lling tree hitting the guys. For

example, a 50-foot-tall tree within less than 50 feet of an anchor must

be cut down.

Note that it is possible to use some

of this cleared area after the met tower has been installed; in other

words,

after installation, the space is left largely open.

Space

availability at the Tri-town sites

Tree clearing will be needed in all cases:

Brandt Island Road

Town Land

High School WWTP

Space availability There appears to be There appears to be

for met towers sufficient level area for a sufficient level area for a

50-meter met tower. 50-meter met tower.

Accessibility for met tower installation

The sites are easily reachable by RERL’s pick-up truck.

Depending on how

much space can be

cleared, this area may fit

a 40 or 50-meter tower.

The power lines on the

access road to the north

and the wetlands to the

east will be constraints.


Nearby Airports & FAA restrictions for met

towers

RERL’s met towers are shorter than 200 feet and do not require registration with the FAA.

Lighting

T he FAA does not require met tower lighting at these sites. The Renewable Energy Trust recommends

FAA lighting of met towers even if not required by the FAA.

If the town opts for lighting, either a source

of 120 VAC power

or sufficient photovoltaic panels and

batteries will be needed as an energy sourc

e for the light.

Distance to power line s (for met tower lighting if used)

If the town opts for lighting, 120 VAC power is close enough in the case of the High School and the

WWTP, that we recommend wiring be run to the met tower bas e. In the case of the Brandt Island Road

town land, unless the town can provide AC power, RERL will install photovoltaics and batteries.

Soil quality & Anchor requirements

Soil quality &

Anchor

requirements

Brandt Island Road

Town Land

Expected to be

acceptable

High School WWTP

Expected to be

acceptable

Expected to be

acceptable

RERL’s standard anchors may be adequate or larger anchors may be required. This will be tested on the

site.

Met tower Size Recommendation:

RERL uses two sizes of met towers, 40-meter and 50-meter,

depending on the site. Because all these

sites are forested, 50-meter towers are recommended:

Brandt Island Road

Town Land

High School WWTP

Met Tower Height 50 meter 50 meter

50-meter

is

recommended

but 40-

meter

may be adequate

if there is insufficient

room.


Summary

The relative merits of the sites for met towers are summarized below. All the sites are adequate

for met

tower installation.

Brandt Island Road

Town Land

High School WWTP

Ease of installation Level site. Can Level site; can

probably use standard probably use standard

anchors anchors

Clearing Trees will need to be

removed

Trees will need to be

removed

Security Unknown Possibly a danger of

vandalism

Predicted wind

resource

Good Lower than typically

desired for the

Community Wind

Collaborative

Conclusion: met tower siting recommendations

Site needs cleanup and

some leveling

Some brush and trees

will need to be

removed, plus debris

Fenced-in site

Lower than typically

desired for the

Community Wind

Collaborative

As pointed

out in the previous section, the met tower should be installed at the preferred turbine site.

To participate in MTC’s Community Wind

Collaborative, the tri-town region should choose the site in

consultation with MTC in order to ensure

the site fits the Collaborative’s criteria.


6. Anemometry Installation Logistics

Site Owner Responsibilities

RERL

is pleased to offer wind-monitoring services to the town through the Trust’s Community Wind

Collaborative. If the site is eligible for MTC’s Com munity Wind Collaborative, and the

monitoring

effort moves forward, the town’s in-kind assistance will be needed in several aspects of installing a met

tower. The host town (Mattapoisett or Marion) would be responsible for security, some

minor

maintenance, insurance, and permitting. They are described

as follows:

Security

T he security of the loaned monitoring equipmen t is the responsibility of the town. The town is expected

to protect the site to its satisfaction – e.g. by installing a fence around the tower base if this seems

necessary. If the site manager prefers, RERL can place the logger high enough up the pole that a ladder

is required to reach it. Additionally, if PV panels were needed for FAA lighting, these would be located

near the base of the met tower.

Maintenance

Met towers have data loggers mounted at the base, to collect the wind data. The data loggers require

that a memory card be periodically swapped and mailed back to RERL. Additionally, the person

replacing the card would look at the tower and report anything unusual to RERL. A designated town

representative

(or representatives) will be trained in these simple operations at the time of installation.

Liability and Insurance

The RERL loans industry-standard wind-monitoring equipment under a standard loan agreement. The

form can be found at http://www.ceere.org/rerl/projects/support/weps/agreement.pdf or contact RERL

for a copy.

The Trust requires that the site owner carry liability insurance for the met tower and name the Trust as

an insured party. This requirement is described in the loan agreement.

Permitting: Local approval process

RERL will support the site owner in obtaining any necessary local permits for the temporary monitoring

tower (e.g. building permits or zoning variances.)

In-kind labor

In-kind labor has been discussed above, in this section. Additionally, the town would do any clearing

needed.

If lighting wiring is required (see notes on FAA lighting above), this is provided by the town.

Weather

The met tower cannot be installed in strong winds, rain, or snow. Additionally, the anchors must be

installed before the ground is frozen in order to be properly proof tested.

Note that weather-dependence can make the planning of the project somewhat difficult. Typically RERL

sets aside a one- to two-week period ahead of time, then chooses the exact days within this window, just

a day or two in advance.


Conclusion: Timing & sequence of events

Met tower installation can proceed when:

1. The Trust approves

the town as a candidate for further community wind assistance

2. The town chooses a location that is acceptable to RERL and Trust.

3. The site owner secures required permits, if any,

4. A loan agreement (http://www.ceere.org/rerl/projects/support/weps/agreement.p df)

is

signed and returned to the RERL, and insurance coverage is confirmed,

5. Anchoring systems have been designed, installed and tested, and,

6. The RERL can schedule a work-crew, equipment – and of course good weather!


7. Conclusions and Next Steps

The Tri-town area

has a parcel of town-owned land in Mattapoisett that is predicted to have winds

sufficient to install a commercial-scale wind turbine. Other town-owned parcels were examined as well.

If the Tri-town area as a group, or the town of Mattapoisett, is interested in pursuing land-based wind

power for municipal use, representatives should confirm their interest

to the Trust.

If project fits within

the Trust’s program, the Trust could then authorize RERL to proceed with wind

resource assessment services. In that case, the following steps are recommended for installation

of a met

tower:

• Consider

a wind turbine site: While a met tower does not have to be at the exact location

of

an eventual

turbine, the choice of turbine site must inform the met tower site.

The Brandt Island Road parcel has better predicted winds, while the High School site has

more space and an electrical load.

• Agree on a met tower site: This should be at or near the wind turbine site under

consideration.

• Met tower size recommendation: a 50-meter tower should be used to better understand the

higher winds and the wind shear in this forested area.

• Permits: determine if any local permits (e.g. building, zoning, etc.) are required for the

temporary met tower. If so, acquire those permits.

• Preparing for the met tower: Sufficient area will need to be cleared at the chosen site. Work

with RERL to mark and clear a site.

More magazines by this user
Similar magazines