In a survey by Panasonic Corp. this September, people were asked about changes in their electricity bills compared to last year. In response, 58% said their bills had increased, while 23% said "not much changed," and 5% said they had gone down. The record-breaking heat this summer is believed to have led many to use air conditioning units at full blast, apparently causing nearly 60% to have higher bills despite the government assistance.

Since energy bills can get painfully high over winter, more than half of respondents answered that they were thinking of toughing it out without the use of heating, with 18% saying they were "strongly" doing so and 35% "somewhat" doing so.

The indoor part of an air conditioning unit.

According to Panasonic Corp., heating tends to consume more power and cost more electricity than cooling. Yet, only 39% in the survey knew this, with the remainder unaware, including 35% who believed cooling consumes more power.

What are some ways to use the air conditioning and heating units efficiently during winter? According to Fuko Fukuda, Panasonic's "air meister," the most important thing is to frequently clean the unit. It is reportedly best to clean the filters once every two weeks using a vacuum or other device. If you go a year without cleaning these, the extra load can apparently increase the amount of energy needed to heat things up by around 25%.

Other efficiency tips include using the automatic air amount setting, making use of insulation on windows, cleaning the outdoor part of the unit, and the simultaneous use of an air circulating fan.

Fukuda also said that not setting the temperature too high is good, with 20 degrees Celsius the recommended setting. For every degree the setting is lowered, there is reportedly a roughly 10% savings in energy expended. This means that plenty of people have room to save on their bills, since around 80% set their units at 22 C or higher.

Fukuda also responded to those who worry whether it's more efficient to turn off the heat when leaving the home for a short while. She said that it's good to keep the unit running when going on outings for no longer than 30 minutes. For times you'll be out longer than that, she said that it is still more efficient to leave it running when the outdoor temperature is less than 3 C, since it takes a large amount of energy to get the indoor temperature back up once the unit has been stopped.

The online, nationwide survey by Panasonic's Eolia brand covered 548 people in their 20s to 60s who use air conditioning units.

According to Mainichi.jp