Sunset Point surfers have lost their east winds due to the Kahuku Wind Farm three miles upwind from the surf spots; new data analysis shows us the loss of east winds is not attributed to climate change. Wind direction is very important to surf quality. Offshore winds are important on the North Shore because they groom wave faces, hold wave faces up and allow them to build taller and steeper before they break, create hollow fast waves, and contribute to creation of larger longer barrels. Onshore winds = bumpy wave faces. Local surfers have noticed significant recent changes in winter wind conditions at Sunset Point since the Kahuku Wind Farm was built. The east and southeast down-valley offshore winds are no longer dominant; east winds are less filled-in/more inconsistent so northeast (side-shore) winds dominate. We now attribute the loss of these offshore winds to the reduced strength of the wind to the 2011 Kahuku Wind Farm because wind data shows us the east winds we used to get are still there – on the upwind side of the wind farm. In the recent period since the wind farm was built, ten-minute average wind speeds are as strong or stronger upwind from the wind farm than they were in the eight years immediately prior to wind farm construction. This new understanding of the wind farm effect to the winds is even more concerning because a new wind farm called Na Pua Makani, which would be 650 feet tall (58% taller than any other wind farm in Hawaii), is proposed at the location just south of the Kahuku Wind Farm (Figure 2), downwind from Pipeline, the North Shore’s premier surf break. This proposed new wind farm would widen the curtain blocking the North Shore’s easterly wind flow. We’re very concerned the Na Pua Makani wind farm will weaken the offshore wind flow at Pipeline. Please consider making a donation to protect our existing wind conditions at Pipeline and Sunset Beach from the proposed construction of the Na Pua Makani Wind Farm at http://www.keepthenorthshorecountry.org/donate/. The proposed wind farm’s endangered bat and NEPA aspects don’t meet State and Federal law, so a court will agree they can’t break ground on the project as it’s currently proposed. Wind farm tax credits expire at the end of 2019.
Description of the Sunset Point Area Surf Breaks: Sunset Point area surf spots include Backyards and Phantoms – Revelations and Velzyland are adjacent surf breaks to the North; Sunset Beach surf break is an adjacent surf break to the south (Figure 1). NE and ENE winds are side-offshore (blowing across the front of the wave face) at Backyards, Revelations, and Velzyland. Due to the way the reef is oriented, ENE winds are more offshore at Sunset Beach and Velzyland. Where Revelations breaks outside/far from shore, NE winds are side-shore. Where Revelations breaks closer to shore, the wind NE and ENE wind is more offshore as the wave face becomes oriented more to the ESE as it bends to the contour of the reef. Therefore, wind that is side-shore when you first catch the wave at Revelations, becomes more offshore on the inside areas of Revelations. The same NE and ENE wind would be considered more offshore at Velzyland and inside Revelations. Surfers prefer east to southeast winds less than 15 mph; wind- and kite-surfers prefer strong NE winds (15-30 mph); many kite surfers avoid Backyards when winds are SE. We refer to winds by their compass direction because “tradewind” can refer to any wind with an easterly component, because wind preferences vary among surf locations and among types of surfers, and because wind that is considered more onshore at one surf break could be considered more offshore at an adjacent surf break.
Figure 1. Locations of existing Kahuku Wind Farm, Proposed Na Pua Makani Wind Farm, two weather stations, important down-valley offshore winds, northeast winds, and surf breaks.
Description of the Prevailing and Local Winds: Our discussion is limited to winter surf season (October 1 through March 31). Prevailing winds are easterly (NE to SE) interrupted by periods when wind direction clocks to the south, west, and north around cold fronts. On days with prevailing wind conditions, the following noticeable patterns regularly occur at the Backyards to Revelations surf breaks: Before Kahuku Wind Farm was constructed (and in periods when it is shut down), around 9 or 10 am, the surf faces become “cleaned up” smoothed off when east or southeast wind flows used to fill in for the day. East winds came directly offshore and down-valley winds often flowed from Kaunala Valley. These east winds and down-valley winds resulted in frequent, perfect, offshore wind conditions at the Backyards, Phantoms, Velzyland, and inside Revelations surf breaks. These east and down-valley winds of varying strength would influence most of the local surf breaks on most days. On days when the prevailing tradewind is from the NE or ENE, the local SE down-valley winds battle with the sideshore winds. They would often meet in the Phantoms vicinity – the SE winds would dominate the nearshore areas and the side-shore wind would dominate at Revelations. When winds were strong enough to be visible on the ocean surface, you could visibly see the SE down-valley winds blowing across the ocean surface to the vicinity of inside Phantoms at the same time you could see the NE or ENE winds blowing at Revelations. Usually, Revelations winds were not influenced by the down-valley SE wind flow – northeast winds always dominate out at this break. Since the Kahuku Wind Farm became operational, east winds and the down-valley winds from Kaunala Valley are much weaker and the east and SE down-valley winds are no longer the dominant wind pattern at the Backyards to Phantoms surf breaks. Due-east tradewinds are coveted at most surf spots – they are offshore at most locations. When a rock wall, large buildings, and large trees come on to the landscape near shore, surfers notice east winds are lessened behind the structure. Having just passed through the Kahuku Wind Farm, east winds are now much less “filled in” at the Backyards to Revelations surf spots. They are much more turbulent and inconsistent. The northeast sideshore winds now dominate. What all of this loss of east and southeast winds translates to, to an untrained eye, to the non-surfer living at Backyards, is that when you go down to look at the wave faces from Backyards to Revelations, you don’t see clean and smooth wave faces as often as you did the years before the wind farm was constructed.
Wind turbines cause turbulence (visible in Figure 2). Because we’d read aircraft safety and other precautions related to turbulence extend only a mile or two from wind farms and Sunset Point is three miles from the Kahuku Wind Farm, we had previously attributed much of the wind change to climate change. Climate Change has had clear and noticeable changes in surf quality, but these changes have been occurring over a long period of time: ocean swells were stronger in the 1970s and 1980s and winds were very frequently strong (18 – 30 mph) and good for wind surfing at Backyards and Revelations prior to 2000. Our analysis of wind data from stations upwind and downwind from the Kahuku Wind Farm indicate climate change is not responsible for the significant change in the strength of the east winds and Kaunala Valley’s down-valley winds. We believe the Kahuku Wind Farm is primarily responsible for the loss of the down-valley SE wind conditions and the inconsistency in the east winds. This new wind analysis alarms us because it shows the wind strength that would feed the down-valley SE winds is still relatively unchanged at the weather station upwind from the Kahuku Wind Farm. This new understanding of the winds is even more concerning because a new wind farm called Na Pua Makani, which would be 650 feet tall (58% taller than any other wind farm in Hawaii), is proposed at the location just south of the Kahuku Wind Farm (Figure 2), downwind from Sunset Point and from Pipeline, the North Shore’s premier surf break.
Figure 2. Wake turbulence is usually not visible to the eye as it is in this photograph. In this photo, the air temperature was very close to the dew point so visible clouds formed when energy was removed from the air by the turbines. The wind turbine disturbance of the visible smooth laminar air flow with eddys and vortices is visible because of the fog (http://www.dgem.nl). (For scale, large windmills are spaced about a half a mile apart.)
Details of Wind Analysis: Figure 1 shows the locations of the upwind and downwind weather stations (green dots) examined in the analysis in relation to the existing Kahuku Wind Farm (installed in 2011 and the North Shore but faltering in early operations due to fires), and the Pipeline to Revelations portion of the North Shore. Winds are labeled arrows. The weather station wind analysis compares wind speed and direction in the period prior to Kahuku Wind Farm installation to the 2012-present period after the wind farm became operational at two weather stations; one upwind and the other downwind from the Kahuku Wind Farm. The wind analysis uses readily available weather data and software – it would take 30 minutes for you to repeat it – contact us if you’d like assistance running the analysis.
The winds at the weather stations behind (downwind) and in front of (upwind) the Kahuku Wind Farm are shown in Figures 3 and 4. We were not surprised to see the changes in wind reflected in the before and after wind rose graphs for the weather station downwind from/behind the Kahuku Wind Farm (Figure 3). The wind rose shows quite a significant reduction in the strength of East and ESE winds after the wind farm became operational. We believe this reduced wind strength due to the wind farm is the cause of the significant reduction in the strength of the down-valley offshore winds at we’ve seen at the surf spots at the mouth of Kaunala Valley (Backyards and Phantoms).
Figure 3. Significant reduction in surf season daytime trade wind 10-minute average wind speeds recorded before (left) and after (right) Kahuku Wind Farm construction/operation at the Kahuku Training Area weather station (½ mile downwind from the Kahuku Wind Farm). Strength of East and ESE winds is significantly reduced after the Kahuku Wind Farm became operational versus before the wind farm was constructed. Winds downwind from the wind farm are squirrely winds from other directions, indrafts of wind blowing in toward the leeward side of the wind farm due to eddys/vortices behind the windmills. We’re relieved the very significant proportion of hours with west winds shown in the recent wind data at this wind farm, which must be due to very strong eddys in the immediate vicinity of the wind farm don’t reach Sunset Point. However, the reduced strength of the East and ESE winds seems to be closely related to the very significant reduction in the periods when down-valley offshore wind direction dominates at Backyards/Sunset Point.
What’s really unexpected is that the strength and consistency of winds at the weather station located one mile upwind from the wind farm are not very different now then they were before (Figure 4). The significant number of hours of consistent strong east winds (the green and blue bars in Figure 4) are still reflected in the upwind weather station’s recent years’ wind data. Because the very significant loss of wind strength we would expect to see if climate change were responsible for the recent significant loss of down-valley offshore winds at Sunset Point is not present, and because the loss of the down-valley winds has been so striking since the wind farm became operational, it’s very difficult for us to attribute the loss of offshore winds at Sunset Point surf breaks to climate change.
Figure 4. The strong consistent daytime surf season winds are still present at the weather station located one mile upwind from the Kahuku Wind Farm. There has been very little loss of trade wind 10-minute average wind speed in the recent period since the Kahuku Wind Farm operation (right) versus the period prior to the wind farm’s construction (left). The green and blue bars in the graph at the right indicate strong, consistent (10-minute average, uninterrupted by wind-farm lulls/gusts) easterly winds are still present at this location (unlike the wind rose graphs in Figure 3 showing data from the weather station situated downwind from the wind farm and the wind we feel at Sunset Point).
On the bright side, we are relieved because the degradation of winds that is caused by the wind farm could be avoided; we’ll ask the Kahuku Wind Farm to feather their blades to minimize their effect on the down-valley, offshore winds at Sunset Point when good swells are registering on the Waimea buoy. We’ll also do what we can to prevent construction of the Na Pua Makani Wind Farm upwind from Pipeline, and if it gets built, we’ll work to ensure blades are feathered when swells are good.
Next Steps: Addressing the Kahuku Wind Farm: We’re drafting swell and wind conditions under which we would like the Kahuku Wind Farm to feather its blades to minimize adverse effects to our surf conditions at Sunset Point October 1 through March 31 during the daytime. We’re working with surf forecasters to develop Waimea buoy swell conditions under which the turbine blades should be feathered to avoid adversely affecting surf conditions. Draft conditions (we are working with surf forecasters to refine) under which we would like Kahuku Wind Farm to feather their blades when wind direction at the upwind turbine at the wind farm measures ENE, E, and ESE: There are essentially four types of surfing: surfing (paddle surfing), wind- and kite-surfing, tow surfing, and stand up paddle surfing. Best surfing: Buoy swell 4-feet, 11-second period or higher and winds under 15 mph; Tow surfing: Buoy swell 10-feet, 16-second period or higher and winds under 15 mph; Wind surfing: buoy swell 4-feet, 11-second period or higher and winds 18-35 mph; Kite surfing: 12-25 mph winds.
Next Steps: Addressing the Proposed Na Pua Makani Wind Farm: It’s not illegal (based on current laws) for the proposed Na Pua Makani Wind Farm to further degrade our surf wind conditions (or to cause significant harm to the Kahuku community), but several aspects of the proposed wind farm don’t meet requirements of State and Federal law. It is, for example, illegal to kill endangered bats without offsetting the take and Na Pua Makani’s mitigation proposal doesn’t even claim to produce one single new bat let alone offset the 51 bats they request authorization to kill. Na Pua Makni also seems to be trying to get a license for a smaller amount of bat take than they will need – maybe to get the project built now and deal with the realities of the project’s actual bat take later. For instance, Na Pua Makani calculated their anticipated bat take based on per-turbine bat mortality at the Kahuku Wind farm (314-foot rotor diameter) though their Na Pua Makani turbine rotor diameter would be a much larger 427 feet. Na Pua Makani also claims their bat take will be reduced by 65% due to implementation of low wind speed “curtailment”, even though curtailment hasn’t proven to reduce bat take at the existing Hawaii wind farms. It’s also worth noting that in 2013, the public requested that a solar alternative to the proposed wind farm be included among the alternatives presented and analyzed in the project’s EIS and that alternative has not been provided. Once the less harmful solar alternative is disclosed in the EIS, we hope the permitting agencies will be hard pressed to select the wind farm as their preferred alternative.*
Keep the North Shore Country, Kahuku Community Association, and several other groups that would be severely affected by the proposed wind farm were granted a contested case before the Board of Land and Natural Resources to help assure Na Pua Makni follows State laws. We are fundraising for Keep the North Shore Country, a 501(c)(3) nonprofit, to help them secure funding to pay for bat specialists and retain an environmental lawyer for the contested case hearings. Keep the North Shore Country’s petition is online here: https://dlnr.hawaii.gov/wp-content/uploads/2016/12/C-1.pdf. The Hawaiian hoary bat information gathered in this Na Pua Makani contested case will be useful in informing any other developer who tries to move forward with a wind farm anywhere near the North Shore, including the Ka’ena Point ocean wind farm and extensions of any permits or licenses for the four very visible wind turbines at Waimea Bay. The information Keep the North Shore Country gathers in the contested case effort would also inform any State or Federal litigation that could be necessary if the contested case hearings fail to cure the Na Pua Makani Wind Farm’s glaring deficiencies. In a Waialua meeting on January 26, 2017, HECO’s vice president and other representatives assured us that future North Shore wind development including the Na Pua Makani Wind Farm is not a necessary part of clean energy plans – they told us they had initially rejected Na Pua Makani’s application and the wind developer had to contest the decision to get as far in the planning stages as they have.
Please Help Us If You Can: Please consider making a donation to protect our existing wind conditions at Pipeline and Sunset Beach from the Na Pua Makani Wind Farm at http://www.keepthenorthshorecountry.org/donate/.
*This is a personal weblog. The information presented here represents the concerns of local Sunset Point surfers, concerns raised by Keep the North Shore Country, and data from contributing weather specialists. The concerns expressed here are not made by or on behalf of any agency or entity with connections to wind farm permitting or authorization