Heating Calculation

It really depends on the heat loss of the building (which will likely exceed any heat absorption benefit). I would think you (may) have a case for increasing the heat of the office area (but not the open factory), but if the office area is open as you say then you would just be throwing good heating after bad.

I think it is probably best to keep the building temperature above freezing when not in use and then use localised heaters to quickly boost the temperature near office (and possibly factory) workers in the morning. The only other argument I can think of is regarding possible increased maintenance costs/failure rates of office and factory equipment due to the cold and/or temperature cycling (I doubt spending money on insulating the office area better to reduce heating and airconditioning costs is a viable option in this case).

As for the plants, well you could replace them with plastic (or something a little more resistant to cold), put them in a warmer place, just take them home or leave them where they are and let the strongest survive.

Don't forget that sometimes for a company to survive the business and economy lows people may need to make some sacrifices (which may be the case here by trying to reduce a large business expense like heating).

We're slowly adding some steps to insulate (plastic on windows, caulking) but we'll do more in the summer for next year. We're very small (7 people) and trying to weather the bad economic situation in Michigan. We've all had to endure cut hours, pay cuts, etc. but thankfully we've landed a few jobs to keep us going...don't want to see 21 years down the drain!

I just don't see that advantage of the heaters being on for prolonged periods of time versus maintaining a lower temperature. It may not make any difference since there is minimal insulation throughout. Just curious and tired of being extremely cold in the morning! I'm thinking of purchasing Snuggies for all employees!

We have looked at our heating cost and, through monitoring the meter, have found our best results to be cut the shop back to 45 degrees every night and cut the office back to 55 degrees Monday through Thursday night and down to 45 degrees for the weekend. Our office has insulation in the walls and about 1' on the ceiling, on top of the drop ceiling.

dgibson...Thanks for the input...looks like my boss may be right (I'll never tell him that though)! I thought of monitoring the meter and such but I know it would become an issue to follow it through, especially since I'll be out of town for over a week and the process would be dropped.

Seems like you did all the research and I appreciate the feedback. We're actually building a job right now that requires space heaters supplied by the customer. They've been slowly leaving the build shelves and finding their way under desks! Hopefully the job will not ship until it's warmer outside!

First, you need to calculate the kWh usage of these heaters and count how many are in the building. Second, inform your boss of this added extra cost and how it could be avoided by programming the thermostat to heat up the building before the employees arrive. Space heaters generally, cost more to operate than furnaces.

Instead of snuggies, try heated seat cushions. The ones designed for cars do not use much power. Remember that it is better to heat the person instead of the air. Radiant heaters may be another solution.

Just look at it this way your plants just got their pink slip. In the process someone else's job was saved. Utilities are part of the over head of run the business and to cut cost a lot of managers have been asked to do the same in these economic times. I would though ask that since they are programmable. That they start to rise the temperature before the before the employees get to work. A compromise of having the set back start 1 hour earlier then quiting time. The building will hold the heat for awhile.

I wish the heaters here could maintain the production floor at 68 deg F. 60 would even be nice. On really cold days I have to set up auxiliary heaters not to make the employees comfortable. To keep the plastics we process in die from cracking.

To get a fair handle on heat loss of the building, time the duty cycle of heaters and multiply their outputs by the duty cycle at a few different times of the day and use the average. If you want to factor in the heat capacity of the furniture, etc. then a fair measure of that will exhibit itself by the length of time it takes it to reach nominal room temperature. Remember Newton's law of heating and cooling? Heat transfer is a function of temperature difference, heat capacity etc., so the factoring-in of heat capacity isn't as straight forward as one would hope.

I totally agree with conserving the heat, especially when I'm one of the people that has to hold back on cashing their check for a few weeks! Luckily haven't had to do that for a month now.

The office thermostat is a smarter one that calculates the need for heat before the designated starting time but the shop one isn't. It will probably be replaced since the hysteresis on it is poor also. We contacted the manufacturer to see if we were programming something wrong and basically got generic answers...yes it's supposed to be 0.5 degrees and yes 2.0 degrees is normal...??? Basically it's junk.

I will miss the plants though...

Have you talked to the local power company, many have energy programs to help the customer to save energy. These programs often have rebate checks for some to all of the work that is preformed. ie: insulation, weather stripping, even new programmable thermostats.

Do you know what your peak demand is and when it is, being able to change your peak could save you $$$ through out the year just by shaving a few points off of it.

Even fans to help pull the heat down from the high ceilings may help with the comfort of some workers.

I could help your situation. Tell the boss to contact me at 631-756-9116x129. My method would save him/her an average 26.3% annually on the HVAC portion of the electric bill. No need to lower the themostats to 45 degrees. And yes, it uses more enegy to bring facility back to comfortable setting.......Greg.

It absolutely does NOT use more energy to bring the building back to normal temperatures. Heat loss is dependent upon the temperature difference between the two spaces. As the inside temperature drops the heat loss drops. If the inside temperature were the same as the outside temperature, there would be no heat loss. It is always cheaper to let the temperature drop overnight and weekends. Most places do not go lower than 55 because the inside walls and other items, such as plants, may suffer damage from the big changes.

You don't think it costs more to bring a building back to temp from 45f to lets say 68-70f ?

Greg,

No, it doesn't cost more. Heat is constantly being lost from a building as long as the outside temperature is lower than the inside temperature. The heat loss is directly proportional to the difference between the temperature - usually referred to as delta T. The rate of heat loss is smaller when the delta T is low. Keeping the temperature of the inside higher has a higher heat loss than if you lower the temperature. Bringing a building back up to 68 from 45 will use less heat than keeping it at 68 all the time. That is why you have programmable thermostats for night setbacks. Here is one other thing to consider however. If the heat source were an electric heat pump with a resistance heat back up, then it might be cheaper to keep the heat up to avoid using the resistance heat during a peak billing period. Cheaper, but not necessarily using less energy.

In the UK, there are regulations requiring the temperature in areas where office work is carried out to be at a certain minimum temperature beyond a period of time after which people have begun their work. Are there similar regulations in Michigan?

• It would be wise for freeze-protection facilities to be operable.
• It would be wise to carry out air temperature recording in areas of doubt.
• It would be wise for the local union representatives to become involved where working temperature regulations exist, so that monitoring and appropriate representations could be made where the operation is not compliant with local workplace regulations.
• It would be wise to re-assess the facility from the perspective of stopping heat getting out:
• Are all the doors and windows draught-excluded?
• Is all the facility's insulation as good as it could be?
• Could low-emissivity glass be installed in outer wall windows?
• Could more be done with regard to lighting efficiency?