[Disclaimer: The following article deals with technology involving heat, electricity and batteries. Use of which can involve risk of harm as well as a benefit. If you do not feel competent to manage these risks then please do not do attempt them. The author will not be held responsible for any misadventure arising from the use of any of the suggestions presented in this article.]
Winter is coming, as it always does. However now the era of cheap energy may well be over. Energy bills have never been higher. The price rises may be from supply shocks due to war or misguided energy policies. Whatever the cause of the high energy prices, there are a number of ways, both old and new, to stay warm without racking up big bills.
Through the long decades of energy abundance we have become careless about energy use. We have had a casual attitude about expending great quantities of energy heating an entire building just for a little of it to rub off on its living occupants.
Some have even set their heating to go on even when no one is home just so it will be warm when someone finally comes. When the energy prices ramp up this extravagance becomes horribly expensive, as we are seeing today.
Understanding this extravagance in heating the air of a building rather than the actual persons directly is how we can have our warmth at a small fraction of the cost. Your walls and your furniture do not need to be kept warm. Only you, your family and your pets do.
Most of the following tips achieve energy efficiency through focusing heating and insulating efforts where it is really needed and avoiding waste. “Heat the person, not the house”, and also we could say “insulate the person, not the house”. This is the basic economic strategy you could also use to innovate your own solutions.
In this section we will explore old and new solutions to bring the heat closer to the person. All of these solutions involve a small capital investment but will allow for very efficient energy use.
What happens when you combine a battery with a heating element integrated into a piece of clothing? You get a man-portable central heating system that you can take anywhere and costs pennies in upkeep.
Designed for hikers and other outdoor activities these augmented pieces of clothing work just as well indoors. Indeed, if you are not heating your house then the indoors is the new outdoors.
These mats are essentially the same thing that makes the heated clothing above work but without the clothing. They are designed to help keep col-blooded pet lizards and snakes warm enough to function in northern climates. They are placed in the bottom of vivariums, think aquarium but for reptiles rather than fish, and plugged into the wall socket.
Typically they run around just 7 Watts so they use very little electricity. Compare with the 2000 Watts that a typical electrical space heater uses. Neither do they produce much heat of course, but if placed against the body they produce plenty for a mammal. Again, heat the person, not the building.
I keep mine on the chair of my home office, see the pic below.
As they are of such low power consumption, they can be powered by usb power connectors. And some indeed come wired that way. This little fact means that they could potentially be combined with a portable power bank to give a fully mobile source of personal warming.
Portable power banks are designed for charging phones and tablet computers on the go, but the power draw is comparable to that of a reptile mat.
Electric blankets are an old solution that old folks may know well. Essentially the same technology as with the preceding solutions. It is an electrical heating element for placing close to skin.
It differs from heated clothing in being less portable for having no battery. And it differs from the reptile mat by drawing more power.
It is still a solid solution for staying warm at a low cost. Designed for sleeping, they could also be with any sedentary activity.
Hot water bottles are an age old solution and the only one here that has the potential to work without access to electricity, if you can heat water by other means (see the fresnel lens below). Water has a very high specific heat capacity which makes it a compact medium for storing heat energy.
Place your hot water in a suitable container that is water tight and heat resistant. Then you have a portable source of heat you can keep close to your body.
Traditionally the hot water bottle is taken to bed but you could use it in other circumstances.
Indeed there are even wearable hot water bottles now.
If you have used the above section to move the heat closer to the person then you also solved the problem of how to insulate a house. There is not so much need to insulate a house if you are not heating it.
That is good news indeed, as insulating a house is quite a big job and for tenants one that is largely out of their hands, as it is at the discretion of the landlord. Usually a landlord would rather you shivered, than spend on insulation.
That does not mean we could not benefit from insulation to the keep the heat where we want it. We just need to move the insulation closer to the person as well.
In this section we will explore to how best to insulate the person.
Heat will get away from you by three different pathways: convection, conduction and radiation. Insulation is about putting up effective barriers on these pathways. The efficiency of thermos flasks, also called vacuum flasks, comes from their ability to block all three to a great extent.
The easiest pathway to block up on a person is convection. Conduction and radiation will transmit your heat to the air adjacent to your skin. If that air is allowed to move away it will take that heat with it.
All basic warm clothing functions by trapping warmed air where it is. The more layers and the thicker the layers, the more barriers.
Regular clothing has some fatal gaps though. Openings for heads, hands, arms and legs introduce highways for warm air to escape. For a thorough barrier to convection consider tucking trousers into socks, sleeves into gloves and tops into waistbands. Or indeed consider onesie solutions like longjohns.
The superstitious may consider wearing a hat indoors to be bad luck but the frugal know that it is good insulation.
There is not really much to be done here. Anything touching your body that is cooler than you will leech heat energy away from you. Not all materials are equally good conductors though. Wood, ceramics, wool and cotton are poor conductors while metals generally are very good conductors.
It might sound nuclear but radiation is a general word for any kind of energy on the electro-magnetic spectrum which includes light and radio waves. Heat energy can travel this way too although the human eye is unable to see it.
Some portion of your heat energy leaks away by this pathway, unhindered by regular clothing. Shiny things will reflect the radiation back. This is how those funny shiny emergency blankets you sometimes see at sporting events work.
I am not going to recommend using emergency blankets for everyday use. They work and are not hugely expensive but they may not work for very long. The adventurous might consider experimenting with them.
This section is for the hardcore survivors.
We are not genetically so very far removed from our ancestors who survived the winter outside wrapped only in animal skins. The reason we find the chill now so abominable is in part due to a lack of conditioning from too much shelter and easy living.
We are mammals and the one decisive advantage that mammals have in surviving in the north of the world is the ability to generate our own body heat.
Use it or lose it. Too much central heating and sedentary habits makes our inner power station rusty from lack of use. Take the ramping up of energy bills as an opportunity to reconnect with your inner cave man.
Be more active. The more your muscles work the more heat they generate. Prolonged exposure to cold will stimulate a special type of tissue called brown adipose tissue. This tissue burns food energy, like carbohydrates and fat, to make heat energy.
Of course fueling muscles and brown adipose tissue requires food and food prices have their own price inflation. I leave it to the reader to decide which is more economical.
If you are on the chubbier side then already have a head start on fuel reserves.
A few more cheap heating tricks to consider that do not fall into the previous sections.
A fresnel lens is a kind of lens that offers a high refractive power for a given weight of material. There are many uses for such lenses but the use we are interested in is the concentration of solar energy for heating water.
Winter is cold because the energy in solar light is relatively low but even in winter there is some and it can still be harnessed for free energy. We might normally think of photovoltaic cells for collecting solar energy. Such cells are complex and delicate and really best for turning solar energy into an electrical energy.
If you want just raw heat then a fresnel lens is a simple, robust and cheap way to use the free energy of the Sun.
We can even use a fresnel lens to store heat energy for the night. Simply use the lens in the day to heat water then store the water in thermos flasks. Decant your hot water from the thermos to fill your hot water bottle.
Take care with using fresnel lens, the heat energy concentrated at the focal point can start fires as well as heat water.
The sun rises in the east and sets in the west, but the further north you are in the world the more time it spends in the south. Even without using a fresnel lens you can harness the warming power of the sun by the strategic use of south facing rooms.
Do not stay up all night, if you can. Get up with the sun and make your most south facing rooms into your day rooms.
There we are, my practical guide to staying warm on a tight budget. What will you implement? What do you do already?