Smart Limiting Electricity Use in High Risk Conditions

From Energy Flips
Jump to navigation Jump to search

Basic considerations

Under particularly difficult power delivery conditions, all consumers may be required to voluntarily reduce power usage to avoid total failure of the power grid which may lead to shortages and, eventually, blackouts. While voluntarily reducing power consumption may not amount to much in actual terms, the perspective of avoiding a highly disruptive blackout is the most important achievement.

The best approach is to understand which devices have the highest impact on the power lines and how to configure effectively the ones that are important. Limiting disruptions on your activity as well as others is highly important.

Global objective

While large and small devices have an important contribution, the most difficult to cope with situation is the instant requirements that can quickly disrupt a power grid with low reserves. This goes against some popular recommendations such as simply turning off lights and limiting heating/cooling.

A quick glance at the watts power ratings printed on the label of most devices can give a rough estimate of consumption potential. Devices that can be instantly turned on and off with power loads in the thousands of watts are the biggest risk to the power grid's stability.

Season specifics


Heating a building, for a commercial or residential purpose, requires the highest amount of energy. Only under specific stressful conditions localized heating, and for particular rooms, shall be exercised. This means that bathrooms and bedrooms should always receive heat from any energy source. In extreme circumstances, only the bathroom may be heated due to requirements of personal hygiene and safety.

Making sure that the building envelope is as airtight as possible is very important. Any water ingress or water release due to cooking will amplify discomfort. Well closed windows and doors as well as microfiber clothing can help in reducing heating requirements. Portable heating devices, if used, should be moved some meters away from cool façade walls to improve efficiency, particularly if they do not have fans.


Cooling buildings is important in summer. The risk of life-threatening conditions due to heart ailments raises significantly during very hot and humid periods of time. This means that only air conditioning devices and refrigerators should be kept on, while anything else could be considered optional.

More intense ventilation in case of openable windows and doors, in less humid times, can reduce reliance on air conditioning devices. In high humidity conditions it is better to limit ventilation as much as possible by ensuring well closed windows and doors and dehumidify/cool only certain areas. Boiling, frying, baking should be limited, if possible.

Essential appliances

There are always essential devices or electricity consumers and ones that can be lived without, in a power crunch. Depending on conditions, the ones that ensure life support, particularly for persons having specific health issues, are deemed essential. This means that devices which ensure temperature comfort should be treated with the outmost attention.

Appliances that should remain off

While lighting, air conditioning devices can be turned off, there are much better consumers that should be used as sparingly as possible due to their large instant power grid demand.

Any electrical cooking device, particularly ones that release heat should be rarely used. Cafetieres, electric kettles, grills, ovens can have a very high impact since they have hundreds of watts of power load that can be many times switched on and off during use, stressing the power grid.

Important appliances

Cleaning and comfort devices are also having a major impact on power requirements. Clothing irons in particular require a lot of energy. Somewhat similarly, hairdryers, vacuum cleaners and other such devices have a major impact due to their instant load they place on the electrical network. Refrigerators require less power and are mostly exempt from this presentation although establishing acceptable temperatures can reduce slightly the daily consumption.

Power food mixing devices may require medium power carrying capability but they are generally less demanding than appliances that heat food products. The smaller the handheld devices are, the lower their power requirements.

Hairdryers and irons

While rarely considered to be particularly important, hairdryers do require a lot of electrical energy, particularly when operating at high temperature settings. If possible, they should be turned to a low power setting and used as close as possible to the hair to increase efficiency and reduce power use. While drying time may slightly increase and there is a slight discomfort, it is preferable to not using them at all.

Standard steam irons are highly energy consuming so their use should be avoided, if possible. A vertical iron requires less than half the power, is easy to use and can be effective for clothing items.

Electric boilers, other water heaters

Electric boilers that prepare hot water are also an important source of electricity demand. The water temperature can be safely lowered by 5 or 10 degrees in the summer, particularly when the weather is very hot and the required water temperature can drop to between 40-50 degrees. When serious risks arise, an accumulation boiler can keep heated water for a few hours when powered off.

Instant water heaters create much larger power grid demands than the tank or accumulation boilers. However, using instant water heaters at low power setting may not be optimal due to lower water flows required for adequate tap hot water temperature results. In this case it is preferable to use them on low power, only for showers, and with low water flows.

Bath heaters also require large amount of power and they may be avoided, particularly early in the evening, when the power demand is still high in city networks. Bathing late at night or early in the morning may be an option for some. When in doubt, hot showers are preferable while cold water local cleaning are options to further reduce power load.

Washing machines

Washing machines should be used without water heating. This saves a lot of electricity and most washing powders and solutions will still be somewhat effective at room temperature water, particularly in summer. Setting a water temperature of 20 degrees on most appliances simply turns off water heating.

Centrifugation does require little energy compared with heating and the washing cycle without any centrifugation uses as little energy as a TV left on for a couple of hours. Lower centrifugation speeds such as 800-1000 rpm can also reduce energy consumption and lowering them further is better than avoiding centrifugation altogether.

Not using prewashing requires less energy. Going for a one hour washing cycle compared with the typical one and half one can also reduce power demand. An even shorter 30 minute washing cycle is rarely as practical, but possible in some cases.

Dish washers and clothes driers

Dishwashers do not use much electrical energy if water heating is turned off. While cleaning efficiency will be diminished, results may still be satisfactory. Their pressure washing system is still much more effective than cleaning by hand.

Clothes driers require a lot of energy to operate, particularly if the device does not use a heat pump. This means that resorting to simple drying on the washing machine instead of relying on the clothes drier may be less power grid stressful.

Vacuum cleaners and power washers

Vacuum cleaners can be operated at lower power settings and they may be still quite effective. Note that high power settings also tend to be noisier and release more heat in the nearby area, a fact that should be avoided in hot summer days.

Power washers may also be high powered devices, particularly if they heat water. Not activating the water heater option or setting a lower power setting than the full one may end in saving water and power.

Cooking machines and microwave ovens

If these appliances are electric powered, their consumption and energy use may be very high. In most cases it requires less power to reheat or prepare certain meals using microwave ovens or induction plates, if the cooking machine does not have induction plates. Although the end result may not be the same, the electricity grid impact will be much reduced with induction/microwave cooking.

While relatively high powered, microwave ovens are the most energy efficient way of heating food or liquids. Using them instead of other appliances is preferable. Some appliances have grill functions that can use additional power. This can be separately turned off to reduce the risk of loading the electricity grid. While further use optimization may be possible, most devices do not reflect how they vary power when heating, if they are capable of that.

Audio amplifiers, public addressing, broadcast systems

Power audio amplifiers generally have moderate electrical energy requirement unless they are used to provide services in large systems or used for various events. Karaoke systems may also require certain power when not active. Turning these devices on and off too frequently, however, may stress them and reduce their useful life.

While technically different, some stage or disco lighting systems can have significant power requirements just as some video projection equipment. The same may go for lighting used when filming. Video processing requires large amounts of power as well.

Signage and amenity lighting

Large outdoor or indoor projectors may be higher powered. Most signage lighting may require electrical energy, particularly if light areas are large. During the day and early in the evening, signage lighting can be safely turned off to conserve energy. Using a flexible LED string to cast light only where it matters in signage or for other purposes can save a lot of electrical energy.

Amenity or product showcasing lighting may also have a certain impact on power, particularly when using older incandescent or high intensity lamps, as was popular to increase the appeal of food. Energy efficient LEDs or reduced lighting should be considered.

Devices with low power impact

Radios and other handheld devices including tablets, phones, small laptops do not contribute as much to power demand, their power load being lower than 15 watts in most instances. While there are ways to limit energy consumption on any computing device, the most practical approach is to use high demand applications and web browsers only when needed.

Lighting, particularly if using LEDs and for indoor applications, require much less power than even a small laptop. Only very extensive lighting systems installed on large rooms may have a slightly larger impact. Fluorescent lamps were and still are reasonably low consumption devices. Decorative lighting may be turned off to save a few watts of power but it does not have any significant impact, most of the time.

A TV or laptop should not use much energy when on or off. Desktop computers have slightly larger energy consumption. Older, cheaper systems may draw energy even when turned off so unplugging them is advised. Rendering, 3D modelling, film editing poses on computer systems requires additional power. Slightly reducing backlight brightness on displays may reduce the power load by a few watts.

Fans, purifier systems, aroma diffusers, particularly household sized ones, have little power requirements and they can be safely used most of the time. Even larger fans for commercial ones still use less power than air conditioning devices or other high powered devices.