Warnings to heed from those who should know
While there are still some people who do not believe climate change is caused by human activity, very few will deny that the climate is changing and that we must adapt to the new threats we face as a result.
Upper-ocean temperature, which is fuel for hurricanes around Bermuda, is increasing. The height of extreme sea levels caused by storms is increasing. Warming is causing more intense, heavy rainfall events.
Research indicates that the frequency of the most intense storms is likely to increase, and that more of these storms are moving farther north.
A look at the historical data shows the one thing that is decreasing is the speed at which these storms are moving, prolonging the duration of heavy rainfall in hurricanes.
During his presentation at the Ocean Risk Summit held in Bermuda this year, Kedrick Pickering, the Deputy Premier of the British Virgin Islands, strongly advised us to diversify our energy supply mix in response to the threat of climate change.
He was talking from experience. BVI took the full force of Hurricane Irma on September 6, 2017.
It was one of the most powerful Atlantic hurricanes ever recorded, with winds that averaged 185mph, gusting to 215mph. Less than two weeks later, the islands were hit for a second time by Hurricane Maria.
Wind is not the only threat. In August 2017, Hurricane Harvey broke all the records after it made landfall at San Jose Island, Texas, as a Category 4 hurricane, which was then downgraded before stalling further along the coastline and dropping torrential and unprecedented amounts of rainfall over the state.
Many areas received more than 40 inches of rain, as the system slowly meandered over eastern Texas and adjacent waters, causing previously unseen flooding.
Last month, Hurricane Leslie stalled for two days, 500 miles east of Bermuda. Nasa’s Global Precipitation Measurement mission satellite passed above the storm and found rain was falling at an average of three-quarters of an inch over a 60-mile area of deep convection.
Had Leslie stalled over Bermuda, we would have received more than 36 inches of rain, which is an event we are not at all well prepared for.
One message that came through loud and clear this year at the Energy Summit from the Caribbean experience is that we can no longer rely on simply projecting historical data for planning infrastructure resilience. We live in a new normal when it comes to climate threat.
Last year, the international credit rating agency Moody’s warned cities to address climate risks or face downgrades.
Lenny Jones, a managing director at Moody’s, said in a phone interview: “What we want people to realise is, if you’re exposed, we know that. We’re going to ask questions about what you’re doing to mitigate that exposure. That’s taken into your credit ratings.”
Belco’s hub and spoke grid is attached to a central generating plant located on land that is shown on plans submitted to the Department of Planning by the utility for the North Power Station, as having an average contour of one foot above high tide, making it vulnerable to flooding.
Last year we saw a series of extreme tides, most notably on October 18 — “King Tide” — a confluence of highest astronomical tide and a warmwater eddy that flooded Town Square in St George and would have put the NPS site under 18 inches of water.
In a perfect-storm scenario, a slow-moving hurricane stalls just north-west of Bermuda, blocking the entrance of Mill’s Creek with an eight-foot storm surge and dropping 30 to 40 inches of torrential rainfall on the island. Wind-driven waves on the resulting shallow lake around Belco increase the level of inundation.
Even in such an extreme case, Belco’s new NPS generators, which are to be installed on pedestals 14 feet above Ordnance Survey Datum, would be OK. However, other generating assets, transformers and transmission lines would be at risk.
It is not likely that Belco would go down completely, but its generating capacity, especially the ability to meet peak demand, could be seriously affected, possibly over a long period of time.
Storm-related flooding is not the only security risk to the central plant: dangerous fires such as the one in September 2014, when insulation around the exhaust system of an engine ignited and in October 2013 when a switch caught fire and took more than an hour to extinguish, also pose a serious threat to our security of supply.
All things considered, it would be more than prudent to heed Dr Pickering’s advice as a matter of national priority and take proactive measures to spread the risk by diversifying our supply mix as soon as possible.
The bottom line is that the more distributed energy we connect to our grid, the more secure our energy supply will be, and, consequently, the more resilient the whole system will become.
Residential and small commercial solar, along with energy efficiency and energy conservation, are valuable distributed energy resources and provide highly diversified energy sources that feed the grid from the outside, thereby providing an important buffer in the case of partial or catastrophic central plant failure.
One thing Irma and Maria did teach us is that properly engineered solar arrays will withstand Category 5 conditions even when other traditional infrastructure are destroyed, as was the case in BVI last year.
During his talk at the 2018 Energy Summit, Leroy Abraham, of BVI Electric, told us it took six months to fully restore 80 per cent of his islands’ pre-Irma capacity. He said there is no longer any demand for the outstanding 20 per cent.
Presumably, those customers lost their homes and businesses or relocated, taking a significant part of the economy with them.
• Nick Hutchings is a member of the Bermuda Environmental Sustainability Taskforce’s energy committee. If you want Bermuda’s energy future to have more renewable energy and you would like more information on how to make a submission, go to betterenergyplan.bm. For tips on saving energy, visit BEST’s website at www.best.org.bm/resources. All other information can be gained by contacting Kim Smith at office@best.org.bm or 292-3782