Heat waves are frequent. Whether they are more frequent than before, or whether they are caused by human activities, i.e. greenhouse gases like carbon dioxide (CO2) emissions caused by fossil fuels, is a question we don’t want to delve into. The debate is utterly conflictual.
Centuries ago, we had very limited information means and scientific knowledge, yet the consensus was unanimous about most environmental phenomena. For instance, everybody believed that strong heat could cause thunderstorms, and so on. Now, on one side of the political chess board, the duration and strength of heat waves is considered a huge problem caused by gargantuan fossil fuel consumption. On the other side, the exceptional character of that phenomenon is denied or considered quite natural. No matter what climate scientists and thermometers point out, the question remains very divisive.
Maybe history books will depict ours like the era of conflicting opinions, when even the spherical shape of our planet is questioned. Time should blur the lines. Flat earth believers could travel to their supposed edge ot the planet, and change their mind. The others will either cook their eggs on their porch table, or will be compelled to admit that there is no human-related climate change.
How ebikes can ease the burden of heat waves
Inasmuch they are more suitable than regular bikes to replace cars, ebikes can avoid some painful effects of hot temperatures on car driving, namely:
- Internal temperature of a car parked in the sun can easily exceed 55° (131 F°).
- When driving, since internal temperature of internal combustion engines can easily reach more than 800° (1472 F°), the heat seeps into the car.
- Air conditioning increases fuel consumption by 15 to 20%, engine overheating and wearing out.
- By hot weather, remaining stuck in a traffic jam is painful and harmful for your health. You would inhale, among other poisonous gases, lots of azote dioxide, a very poisonous gas produced by car exhaust pipes interacting with sun rays.
- Scorching sun rays wear out every rubber parts of a car, be it windshield joints or tyres. The latter are more quickly consumed by hot asphalt.
- Hot sun fades car paints.
A pause can ease the burden of the heat
Riding ebikes in the heat
As a rule of thumb, we should avoid strenuous physical activity in hot weather, as the World Health Organisation (WHO) recommends. Riding in the extreme heat can exacerbate underlying illnesses including cardiovascular disease, diabetes, mental health, asthma, and can increase the risk of accidents and transmission of some infectious diseases. Heatstroke is a medical emergency with a high-case fatality rate.
Up to 36° (96 F°), riding is refreshing
When riding, the effects of the air flow hitting our body are proportional to our speed. Given that heat always flows from warmer objects to colder ones, riding your ebike with a temperature up to 36° is refreshing, compared to sitting or walking with the same temperature (see for instance Paul Menconi, Energy Auditor). But when the temperature is hotter than 37° (98.6 °F), the faster you ride, the hotter you become, damaging your health and exhausting your heart and muscles. Should the air be 39° (102.2 °F), your body will reach that temperature. The higher your speed, the sooner.
According to the WHO, in temperatures above 40 ˚C / 104 ˚F, even fans will heat the body.
How to prevent overheating when riding with more than 37 ˚C / 98.6 ˚F
- If your body or even your T-shirt is wet, evaporative cooling can cool you even if the air flow is warmer, provided that the water continues to evaporate while you ride your ebike. Air warmer than your body (say 100F/38C) can cool you if you perspire (and most people do!). The warm air evaporates the moisture, which absorbs heat when it goes. That’s why moisturising your clothes and your hair is a good way to better withstand the heat while riding your Ebike.
- Air flow stops cooling your body and starts heating it when the air is warmer than your body temperature.
- Wear fresch clothes, possibly white.
- Don’t forget to hydrate, drinking before, during and after riding. Why not freeze a bottle of water the night before leaving so as to drink cool water all day long as the ice slowly melts? Just fill it only 80% up, otherwise the augmented volume of water turned into ice will break the bottle.
Heat effects on ebike motors and batteries
Extreme heat causes the internal resistance of the battery to increase, involving that more energy is converted into heat in the battery cells, since the hotter the temperature, the faster ions move. This energy is missing from the motor and inhibits the performance of your ebike. Moreover, extreme heat, which in the worst case can cause a short circuit, damages battery cells. Generally, heat, even if not extreme, accelerates battery wearing. Charging a hot battery can harm it, prevent charging or slow it.
Riding in very strong heat can damage and wear out ebike motors. Several gears in the great majority of ebike motors are made of plastic. Extreme heat can dilate metals and plastic, the latter suffering even deformation. A hot motor consumes more electric energy, is slower and noisier.
Riding in hot weather, remedies for your ebike
- Stopping for a good 10 minutes, having parked the ebike in the shadow is always beneficial. Should you have difficulties sheltering it from the sun, you can always lay a white fabric on the battery, to shield it. Reckon that, if you want an ebike with intube battery, a white or light colored one stays fresher in the sunlight. If you’ve got a hub motor, sprinkling it with freshwater can also help. Avoid doing that with the mid-motor, most of them are not completely waterproof.
- Consider that motors and batteries are cooled by airflow, which increases with speed. Therefore, a steep climb can overheat them all the more, not only because the speed is lower, but also because it demands more electric energy.
- So, try to use a lower level of assistance when coping with a steep, long climb in the heat.
- Avoid charging your battery when it’s too hot, let it cool down for at least 15 minutes. Also, don’t leave it charging in the sun when it’s too hot.
