Renewable Energy Performance Evaluation

Solar Island Energy

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Trying to Reason with Hurricane Season

With the coming hurricane season, it is important now to think and plan ahead for the safe operation and maintenance of your property overall and specifically your PV system.

Solar Island Energy has been a contributing author to the 2018 and 2019 authoritative publications on hurricane survivability for PV systems in the Caribbean region. Please contact us to discuss best practices in hurricane survivability related to resilient energy systems. You can request a free copy of these reports by sending us a contact request.

For projects that are considering construction during hurricane season, we recommend the following comprehensive approach be part of the Construction Safety Plan. This is part of all of our regional project plans.

HURRICANE-SEASON PLANNING, MONITORING, & RESPONSE

Planning is the best measure to ensure survivability and minimize loss during a hurricane. The greatest threats to a renewable-energy construction site during a hurricane are damage, overturning, and loss of shipping containers, followed by flying debris, electrocution, rising water, and loss of power.

The goal of the following measures is to manage the risk while introducing the least disruption into the construction process. Some or many of these steps may or may not apply to the specific job site, and professional judgment should apply. As always, Builder’s Risk casualty loss insurance procedures take precedence over this checklist.

SHIPPING CONTAINERS EXPECTED TO REMAIN ON SITE DURING HURRICANE SEASON

Placement of shipping containers when delivering and staging on the site is a critical planning task. Once placed the first time, containers usually cannot be relocated.

The overturning moment from the long side of a 40’ shipping container can be as much as 100,000 foot-pounds. (160 mph would be 70,000 ft-lb.) This is resisted by the weight of the contents and tie-down straps/anchors. Empty containers are at the highest risk of overturning and being displaced, possibly harming persons, destroying other property, or destroying work in progress. At the other end of the scale, a full container of PV modules probably cannot be turned over by just the hurricane winds.

Always place container clusters close together, shielded as much as possible by buildings or vegetation. Allow enough separation from buildings or vegetation to embed anchors into the ground, if required.

Up to five (5) containers can be placed next to each other separated by less than six (6”) inches each. Containers expected to be emptied first should be placed in the center of that cluster (such as racking) and those expected to be emptied last placed at the outside of the cluster (such as PV modules). Rachet tiedown straps (“come-alongs”) and anchors rated 8,000 to 10,000 pounds each should be positioned at 4’ intervals across the top of the cluster.

Typically, a 4’ auger screw, or a helical pier, cable anchor, or rock anchor has 10,000 pound pull-out strength in their appropriate soil base. When in doubt, consider using 10 of the racking foundations on each side of the cluster.

The risk to the modules depends on the weight of the contents. For reference, a 40’ container full of PV modules does not require any tiedown (if it is not damaged). The overturning moment from a 180 mph wind is more than resisted by the weight of the PV modules. Once the container is emptied, it becomes more susceptible to overturning.

PROJECTS SCHEDULED DURING HURRICANE SEASON

Review this Safety Plan hurricane section to ensure the project team knows what to do when a storm threatens.

Establish who will take site control during a hurricane event, if not the Project Manager (any phase of this section of the Safety Plan). This person will manage the plan and assign roles if necessary.

Separate the responsibilities into separate teams for different phases if that is appropriate.

These procedures apply to projects that are underway between June 1st and November 15th.

INITIAL MEASURES AT START OF HURRICANE SEASON

  1. Project Manager shall ensure there are appropriate and adequate supplies of the following on site, and the location(s) of supplies shall be posted on the wall of the construction office.
    1. Duct Tape
    2. Garbage Bags
    3. Screw-type ground anchors
    4. Plastic Sheeting
    5. Submersible pumps for any critical below-ground excavations
    6. Come-alongs
    7. Rope
    8. Water
  2. Print multiple water/rain resistant packs containing the following printed information.
    1. Emergency evacuation plan
    2. Emergency contact information for employees
    3. Vendors and contractors who can provide recovery services and replacement supplies
    4. A contact list of back-up personnel to call if recovery teams are unable to return to work

EVERY DAY DURING HURRICANE SEASON

1)       Monitor NOAA weather, and include status and outlook in Daily Reports.

2)       Do not allow trash to accumulate above 3/4 of dumpster capacity. Ensure dumpsters can be securely locked closed.

3)       Remove coconuts and loose palm fronts from trees once a month.

4)       Monitor activities on neighboring properties for potential wind-blown hazard accumulation.

5)       Remove equipment from secure storage only to the extent that can be completely installed, secured, and torqued within two (2) days. This applies mostly to PV modules, but also to racking parts, inverters, conduit, conductor, and other BOS.

TROPICAL DISTURBANCE POTENTIAL TRACK AREA

  1. Police work areas daily for debris, trash, tools, materials, or any other loose objects that can become flying projectiles during hurricane winds.
  2. Review and adjust project work schedule to limit long-term tasks, such as pouring concrete or erecting structures.

TROPICAL STORM OR HURRICANE WATCH

  1. Stop or delay OUTDOOR construction activities that require more than one day to complete.
  2. Notify Project Manager of the stoppage or delay of work.
  3. Replace or empty the construction dumpster.

TROPICAL STORM WARNING

Tropical-storm-force winds are less than 1-2 days away.

  1. Complete work on partially completed structures to minimize damage, if time allows.
  2. Stop all OUTSIDE construction activities, and limit construction to indoor activities and storm preparedness.
  3. Secure outdoor equipment and materials that cannot be moved indoor or to shelter.
    1. Stack loose materials together and secure them with rope or duct tape.
    2. Use plastic sheeting as necessary to prevent water damage.
    3. Use come-alongs, rope, or ground anchors to secure outdoor materials.
  4. Remove the construction dumpster or cover with a tarp and secure with ropes or come-alongs.
  5. Remove or tie down portable bathrooms.

HURRICANE WARNING

Hurricane-force winds are less than 1-2 days away.

  1. Stop all construction activities, and limit site activities to hurricane preparedness.
  2. Dismiss non-essential personnel to prepare home or shelter for the storm.
  3. Notify Project Manager of the work stoppage and personnel changes.
  4. Mobilize a portable generator of a capacity to power emergency equipment with at least 4 days of fuel available.
  5. Move equipment and materials offsite, indoor, or to shelter.
  6. Secure equipment or materials that cannot be moved or removed.
    1. Stack loose materials together and secure them with rope or duct tape.
    2. Use plastic sheeting as necessary to prevent water damage.
    3. Use come-alongs, rope, or ground anchors to secure outdoor materials.
  7. Board up door, window, or other openings in structure(s).
  8. Complete work on partially completed structures to minimize damage, if time allows.
  9. Consider and plan that any materials left outside of a protected structure may become projectiles or disappear from the site during a severe hurricane, including concrete blocks and unsecured shipping containers.
  10. Consider that during a hurricane the doors and windows of a structure may be destroyed, allowing wind and wind-blown water to enter the structure.
    1. Move equipment and materials away from doors and windows.
    2. Stack loose materials together and secure them with rope or duct tape.
    3. Do not shelter personnel and loose materials in the same part of a building.
    4. Use plastic sheeting and duct tape to prevent water damage.
  11. Secure all project equipment and materials that must remain outside, using come-alongs, rope, or ground anchors on all sides and directions.
  12. Remove the construction dumpster.
  13. Remove or tie down portable bathrooms.
  14. Hazardous chemicals
    1. Remove from the site.
    2. Do not store inside any structure that may be used as planned or unplanned refuge for personnel.
    3. Put inside a structure ONLY if that can be done safely per the MSDS and considering that wind and water may enter the structure.
  15. Remove equipment, materials, or tools that may be damaged by heavy rain or rising water – note these NEMA ratings:
    1. NEMA 3R will NOT protect inside of enclosure from water damage during a hurricane.
    2. NEMA 4 (IP55/56) includes hose-directed water, but not a hurricane.
    3. NEMA 6 (IP67) better resists hurricanes and limited submersion.
  16. Move construction equipment and machinery to a garage or other structure for protection of the equipment and personnel.
  17. Remove temporary fencing, screens, and job-site signage.
  18. Turn off all electric circuits to systems, tools, and equipment.
  19. Place pumps in excavations or basements.
  20. Evacuate site.
  21. Notify Project Manager of evacuation.

POST-STORM RETURN AND SURVEY

  1. Before entering the job site, visually inspect for potential hazards.
  2. Use care when walking in standing water to avoid sharp or jagged objects or foot traps.
  3. Use care when entering a building in case structural elements are compromised.

Solar Island Energy