When the cold dry air from the mountains meets the hot and humid air, you've got the best possible conditions for lightning. The storm clouds build up to an altitude of over a kilometre. Within an hour of the storm clouds forming, the lightning starts flashing. The flash rate quickly accelerates up to flashes per second. A typical lightning storm lasts for 10 hours, and this happens nearly nights each year.
The clouds are like an enormous light bulb, flashing in the sky. It's bright enough to read a newspaper in the middle of the night. The storms reach their peak in September, but according to the locals, the prettiest storms happen in November each year.
These storms are so powerful and so regular that they have been used by European navigators for the last four centuries as a natural lighthouse. In fact, they're nicknamed 'Maracaibo's Lighthouse'. So we've come to the right place to develop the technology to capture and use lightning.
But before we start thinking about lightning rods and enormous banks of tens of thousands of giant ultra-capacitors, let's take a look at what the scientists would call the numbers. Typically, each lightning bolt carries about megajoules MJ of energy. What does that mean in plain English? First, MJ is the amount of energy needed to run an average Western house for about a week.
Second, MJ is the amount of energy in about 38 litres of petrol or gasoline or about 10 US gallons. And third, MJ is enough energy to boil about 1, kettles of water. Did you know Great Moments In Science is a podcast? Suppose that we could capture all the energy from all the 1. In that case, we would have enough energy to make cups of tea for each human on the planet, each year. That works out to a cuppa every three or four days.
Now that's quite surprising. Instead, all it would do is give you a few cups of tea each week. Even though lightning is very impressive, it's no match for the energy-hungry society that we humans have developed over the last few centuries. With no trouble at all, we can easily burn more than 38 litres of petrol in travelling from one Australian capital city to the next—and that's the amount of energy in just one lightning bolt.
So harnessing lightning can't compete with fossil fuels, but it's still enough for a cuppa, so enjoy that zap of energy while you can. Editor's note: An earlier version of this article stated that 38 litres of petrol or 4. In fact, 38 litres is 10 gallons.
As efforts to decarbonize the global economy gather pace, new large-battery storage facilities are being built around the world at lightning speed. Intended to support the expansion of renewable energies and compensate for power fluctuations in energy grids, the U. Department of Energy has recorded more than 1, storage facility projects worldwide, including nearly lithium battery facilities.
However, with the technology involved still in its relative infancy, little information is available on which to base risk assessments from an insurance perspective. This article aims to provide a useful overview of losses to date, important fire protection measures, and underwriting guidelines for Property underwriters tasked with evaluating the exposure of these facilities.
They consist of one or more modules in which accumulators are combined into groups. The individual batteries usually fill floor-to-ceiling racks and the overall storage capacity is usually only limited by the space available to accommodate the storage modules. Such systems have storage capacities upwards of approximately 50 kWh. They are constructed as standalone objects, either indoors or outdoors and contain all the components necessary for their operation e.
Relatively simple and inexpensive to build, maintain and operate, a large increase in the number of plants is expected in the coming years. These storage systems also represent a simple and inexpensive option for stabilizing the power grid, storing electricity, and managing peaks and troughs in power generation from renewable energy sources. According to a study by Navigant Research, more than 28 GW of lithium batteries will be used for stationary storage applications by Given their ubiquity, and the specific problems they present, they are the key focus of this article.
Fires in large-scale battery storage facilities are not uncommon and include the following:. Finally, although not a large-scale battery storage facility, another loss worth noting occurred in a storage building in the U. Due to the enormous amounts of smoke and clouds of pollutants, more than 1, people had to be evacuated before the fire brigade brought the fire under control using tons of dry Portland cement.
The triggers for such events are many and varied, ranging from production errors during cell manufacture to external influences. The investigation of the South Korean fires — revealed four typical causes: Exothermic reactions can lead to a thermal runaway — a chain reaction that leads to a decomposition reaction producing massive heat and gas development in the cell — which spreads quickly to neighboring cells.
Large amounts of heat as well as flammable and toxic gases — such as carbon monoxide CO , hydrogen chloride HCl , hydrogen fluoride fluoride HF , and also heavy metal compounds — are released.
This formation of flammable gases can create an explosive atmosphere inside a battery room or container. Fires triggered by exothermic reactions proceed quickly, intensely and with massive smoke development due to the cell materials used. In the case of thermal runaway, rapid extinguishing is not possible; the only option is to stop the process by continuous cooling. Since this is a chemical reaction of cell components, it should be noted that after the cooling measures have been stopped, a new ignition can occur at any time — even hours or days — after the fire has supposedly been extinguished.
This can only be counteracted by intensive and permanent cooling of the affected cells or quarantine storage of the damaged cells until all electrical energy has been discharged. Attempts to limit the effects of fire with extinguishing systems e.
Accordingly, guidelines and standards are being developed worldwide detailing the planning, construction and running of large battery storage facilities.
Whether the facility is located in a building or outdoors is a crucial factor. As previous losses have shown, fire brigades have a significantly better chance of fighting fires in open areas, simply because of the accessibility. For systems set up outdoors, the distance should be at least 20 metres. For facilities located inside, the bulk storage area should preferably be located at the outer edge of the site and be easily accessible from outside.
It should also be separated from the rest of the building by fire walls, or at the very least constructed as a fire-resistant partitioned space. Such a space should be divided into several smaller sections by further fire-resistant walls to reduce the ability for a fire to spread. To have a chance to bring a battery fire under control, fire brigades need to be able to intervene as swiftly as possible, ideally while the fire is still in its early stages.
The following measures are recommended:. Some of the causes of large-scale storage fires in South Korea have been attributed to poor construction and lack of experience on the part of the design and installation companies. Therefore, companies must be selected carefully, and inspections should be carried out regularly during the construction phase. Once a plant is in operation, monthly checks and thermographic inspections should be conducted with the help of a defined maintenance plan.
Any deficiencies found should be rectified immediately. For example, this includes measuring the internal resistance of the cells, checking for leaking liquids, force-locking of the connections and checking cables and lines for damage.
Other measures include the designation of rescue and escape routes which are also possible attack routes for the fire brigade , equipment and marking of fire-fighting equipment, marking of the hydrant system, training of operating and maintenance personnel on the particular hazards, and other fire protection measures deemed appropriate for commercial operations.
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