Lights. Get a rechargeable, omnidirectional camp light that has a solar panel, dynamo crank and also takes standard batteries. They last 6-8 hours per charge.

Each person ideally should have a headlamp

Candles are good for burning down houses. Buy a fire blanket.

Warmth in power outages

Some ideas that might help. I've been homeless and I've lived off grid on and off for years.

First off, light is easier to produce than heat.- remember that.

Insulate your windows. They are often the place that allows the most heat to escape.

You can get UV blockers that also help with insulation. They also help keep out the heat in the summer.

Put bubble wrap, if you can, over the windows. It really does help. I buy rolls off Amazon or from Walmart. This also helps in the summer heat.

Put plastic sheeting over windows either outside or inside. I have cats, so I put greenhouse plastic on the outside using removable gaffer tape. Then I mark the plastic so it can be taken off in the spring and put back on that same window in the fall.

If you can afford it, you can make rigid panels for each window with Reflectix. They have tutorials for use in RVs but they work even better in a house.

Use towels and sheets over curtain rods to further insulate the windows. Remember light is easier and takes less energy to produce.

I use curtain rods over each door to hang blankets. This insulates the doors. You can also isolate cold hallways so you aren't heating empty space.

I put blankets over the exterior doors to prevent heat loss. I close the door before I push aside the blanket. This seriously helps with heat loss.

Have an off grid way to heat at least 1 room. This one room will need to have room for everyone to sleep and eat.

Have sleeping bags and wool blankets. A wool blanket can take a cheaper 3 season bag up to a 4 season bag. Fleece bag liners also help and are easier to wash than a full sleeping bag.

Have wool socks. They have the ability to be damp and still keep you warm. Have long johns. If you don't have long johns, panty hose can help keep your legs warm. But seriously invest in at least 1 pair of long johns.

Have a pair of wool mittens. If you ever have to sleep without heat, they can keep your fingers from frostbite. Your fingers being together and share heat better than in individual gloves.

Have ear protection in the cold. Cudos if it is wool.

You can also put up a tent as it will help contain body heat. It is best for 2 people to share body heat and invite in the family pets as their temperatures are several degrees higher than that of humans.

Have an off grid way to cook. A BBQ grill will work for most of the year but not necessarily in heavy snow... Unless you are from places like upper Wisconsin and can BBQ in shorts in the winter. (My roommate did this!)

So have something like a portable propane camping stove or a butane stove. Even a small kerosene stove will work for a short time inside. Cooking will also really heat a room.

For off-grid heat, there are several choices. The cheapest is a single burner tank top propane heater. It can heat about 80-100 sq ft. If you already have a 20lb tank, they work really well and can heat steadily for 3 days or 5-7 intermittently. Menards had no name brand ones last year for under $20 on black Friday. So if you don't have emergency heat, definitely shop the black Friday sales.

It is best if you have a battery powered CO detector or better yet, an explosive gas detector/CO detector when using propane and butane indoors.

There are larger ventless propane heaters that are more expensive and you will need large tanks for those. So purely for emergency heat, names like Mr. Buddy and Mr Heater are your best options. They really only have the no name brands on the small tank top heaters AFAIK.

There are also kerosene heaters. Although some Western and Midwest states have outlawed their use inside, they are a viable way to heat inside. I used one for 10 years and now a friend is using one at a cat sanctuary. The first burn needs to be done outside as "burning in" the wick produces smoke. (YouTube videos) But after that, it is just a smell you deal with. They have kerosene treatment that helps with the smell. 5 gallons can last 4-5 days. And if you don't have children, you can take off the safety grills on some models and use the flat top as a cooking surface for Dutch ovens and cast iron. It gets extremely hot, so a diffuser plate is recommended even with a heavy bottomed Dutch oven. And again, you need a CO detector and functional fire alarm to be safe. There are even vented kerosene heaters used in places like Alaska that work with large kerosene tanks outside.

Next is diesel heaters. They originated with Naval use in various countries and transferred over to long haul truckers for use in their sleepers. Now they are popular in Van lifers and in RV groups. They must have DC power source to run the pump but they are very cheap (most of the time) to use. There are specific FB groups that can explain all about diesel heaters. But if you have a farm with large diesel tanks, they are a very cheap way to have emergency heat. Bonus as they also can burn cleaned cooking oils or various other oils in emergencies.

BEWARE of trying to produce heat with candles. If it's very dangerous. They need to be on a fire blanket at the very least. WITH NO PETS AROUND. Not only that but they provide minimal heat, only enough for a very small (closet) room.