Need the ideal heating system

J. Zettner

for a new school would be...?
I'm on the board of a school that is looking to build a new school, (maybe 80,000 sq.ft) in South Eastern Michigan.

What type of heating system (steam, radiant, geothermal,etc) would you reccomend for efficency, dependibility and low life cycle costs?

What type of system if it was to include air conditioning?

Thanks in advance for your time,

John Zettner

Mark Eatherton1

Briefly...

A radiant floor heating system powered by hydrogen fuel cells, geothermal with active solar interface and cooling provided by the air system and augmented by radiant cooling in the slab.

The solar would provide the majority of the hot water needs, with the excess being used to augment space heating needs through the radiant slab. Maybe a small co-gen system to handle peak loads.

ME

ME

J. Zettner

Ideal system

Interesting...

Do you know of such a system in operation?

I've followed Dan's remarks about his European travels. Wondering what is most successful over there?

J. Zettner

GMcD

School Heating Systems

I assume you've done a "Google search" for keywords like "high efficiency school heating systems" and variations on that theme? Lots of hits. The building itself is the "system" that needs to be designed as a high performance Building System. Start with the envelope, and especially the glazing and orientation for winter solar passive heat, high thermal performance, opening window panels for occupant control, reduced solar heat gain in the late spring/early fall seasons, demand based ventilation via either transfer fans or individual classroom systems (unit ventilators with air to air heat recovery sections). Because of the high ventilation requirements of a school (20 cfm X # students), most energy effciency gains are found by dealing with outdoor air ventilation control and heat recovery. If the building envelope is tight, then the rest of the building heating and cooling requirements are minimized to only local systems (computer classrooms, admin. offices, etc.). Once the basic building is designed in a "building physics manner", the actual mechanical plant can be "whatever". The economics and budget will dictate how far you can go with the mechanical plant- condensing boilers, geothermal, solar, etc. Check out this website: http://www.greenbuildingsbc.com/new_buildings/projects_update.html and see what is happening out here with respect to schools. The key is having a well educated building design team who know what they are doing in the first place, and getting the rest of the building occupants, maintenance staff and board to buy into what some might consider "novel concepts" and the address the mythical "green buildings cost more" misinformation.

Eric

Schools

Most often the bottom line is whats the budget.

Also. Who is going to work on the system. The janitor or do you have a maintenance stafff or contract?

Also depends if its a new building or retrofit system.

Noise is a huge factor. ASHRAE had a very good article several months ago about noise in the classroom.


Typically, for a simple school design I would ask for the following.

Number 1 priority!! SPACE FOR MECHANICAL EQUIPMENT. Your Engineer will battle Architect for space. Make it a priority. Adequate space for equipment and ductwork. This will allow for proper mainenance and sizing.A larger duct which equal lower velocity and less noise.

Second: UNITARY EQUIPMENT STINKS. GO WITH CENTRAL SYSTEMS. Less equipment, less maintenance, less controls.

Ventilation. Lots of strategies but this is your big energy savings area. Due to load mentioned above (though classrooms are 15 cfm/per in IBC.

Spend $ on good quality equipment. Custom double wall AHU's. (NO cheap commercial units),Boilers, ect. FOLLOW ASHRAE 90.1 FOR ENERGY EFFECIENCY (NO ACCEPTIONS).

Provide hydronic perimeter heating. This allows for big HP fans to be shut off at night and provide night setback heating.

Limit glycol use only if neccessary and provide automatic makeup package. Axiom and wessels are nice.

Most schools will require a ventilation system. Provide a VAV with perimeter heating. There are some thoughts on dedicated OSA systems, (not applicable for my climate, alaska)

Just my thoughts.

J. Zettner

New School Heating

Thanks all for your good advice, keep it coming.

We've met with several architecture firms and have narrowed it down to two. Our CPA has notified us we may not be able to raise as much money through bond sales as we had hoped and so may have to scale back plans some what.

I will also have to convinvce some on the board that money well-spent on HVAC means lower cost in the long run.
Will keep you posted.

Thanks again,
J. Zettner