Posts Tagged ‘HVAC engineer’
Advanced Energy Efficiency for Buildings
ASHRAE (the American Society of Heating and Refrigeration Engineers) is in the process of releasing booklets free to all interested people with practical step by step information that makes a building design save a projected 50% of the energy bills of conventional buildings being designed. To keep things simple, ASHRAE dedicates each booklet to a specific type of building: small offices/retail/warehouses/motels/educational/smaller healthcare facilities. These booklets are part of a long term commitment by ASHRAE to help create a world where buildings use dramatically less energy. The first stage was to release booklets that describe step by step information on how to save 30% on energy buildings being designed. I had mentioned these booklets on my home page. The new stage is 50% energy reductions. So far one free booklet is available in this category (for small offices). By the time you read this, there will probably more types of buildings available. In the future, expect guidelines for even higher energy targets. By the time 100% energy savings is a reality-buildings will likely need to be linked together with surrounding buildings in terms of energy features (like co-generation, waste heat recovery etc). ASHRAE (the American Society of Heating and Refrigeration Engineers) is in the ...
Florida ground geothermal
I get asked quite a bit about saving money on wells by simply using the ground (or shallow ponds) as a geothermal source in Florida. The fact that this practice is successful in other parts of the USA can weigh heavily on building owner's minds. The math of the situation in Florida is that the sun beats down heavily on the ground at our latitude. As sun bather's know, the angle of the sun on one's body has a lot to do with how much solar heat one takes in. This hurts the geothermal situation in two ways. First the ground (or surface water) absorbs more heat at the very time of year we want to get rid of heat. Second, amount of heat buildings in Florida need to get rid of increases too. I actually tried out the saying that one could fry an egg on the sidewalk at the peak of summer sun. It did indeed cook and make a mess. A 35 foot deep lake is reported to contain a bottom layer of stratefied colder water, but anything less is going to be dominated by the sun in Florida. Unlike northern climates, our winters are not that cold so heat buildup in ...
Geothermal Myths
1. Geothermal is completely sustainable. (Depends). Geothermal in Florida uses the stable temperatures of the earth to benefit (not eliminate) mechanical cooling and heating processes. There will always be electricity needed for compressors and pumps ( in Florida). As geothermal grows in popularity, the effect on the ground water temperatures remains to be seen, but the vastness of the Floridian aquifers and the fact that they drain out into the sea has to be factored in. Geothermal in other parts of the country can be completely sustainable. 2. Geothermal is always the best system. (false). Geothermal has an undisputed advantage where heating and cooling occur at the same time. Cooling towers, for example can boast better performance during Florida winters. Multiple ductless systems at times have the advantage. Geothermal is not as conducive to high outside air as other types of systems. 3. Well drillers are experts who should be allowed to do their own thing. (False). While well drillers are the local experts on the aquifer systems, they are not engineers and have no workable knowledge of interfacing the well pump with the controls or the connected equipment. 4. Variable Frequency Drives solve all pumping problems. (false). Used correctly, VFD’s are powerful ...
What is Geo-thermal?
What is Geo-thermal? Geo-thermal is a process of using the stable temperatures within the earth to benefit heating and/or cooling processes. In some parts of the world, where there is volcanic activity (relatively near the surface), geo-thermal means boring deep down into the earth and pumping very hot water to drive power generation. This is not the same thing as geo-thermal in Florida. In similar parts of the country, geo-thermal can mean boring 1000 feet deep to pump out reasonably warm water to use in selected heating processes. This is not the same thing as geo-thermal in Florida. In many parts of the country, geo-thermal means burying large quantities of piping just below the surface of the earth or below the surface of a lake. Water is pumped through these pipes and used by heat pumps. This is not the same thing as geo-thermal in Florida. Geo-thermal is Florida is taking reasonably cool water in the state wide aquifer system and pumping it through heat pumps, which heat and cool buildings and pools. The water is returned back into the aquifer. It is easy to read or hear of geo-thermal being used successfully in one part of the world and assuming that is what people are ...
Photovoltaic performance
I had a chance to experiment with a photovoltaic cell to see how the performance varied with sun position. I found it easy to decrease the performance of the photo cell by 10% by pointing the cell slightly off a direct angle of incidence with the sun. It was a lot harder to cut the performance below 50% by changing the orientation of the photo cell. The 2V cell I used was normally matched with a 1.5V battery. There was a nominal voltage produced no matter what (clouds, pointing way off from the sun etc.)
solar powered exhaust fan
[caption id="attachment_107" align="alignright" width="300" caption="installed fan"][/caption] I just installed a photovoltaic exhaust fan on my attic. I bought it from Lowe's for $230. I wished it moved more air than it does but definitely noticed a lower pressure and temperature in my attic which means better indoor air quality plus reduced air conditioning bills. Even with code required attic vents already present, pressure in the attic climbs dramatically in Florida to the point where hot dusty attic air pushes it's way into the house through tiny openings in the ceiling. This is even worse when a bathroom fan or dryer is operating. The quality of the fan housing was very good. It was easy to install. I did have to install it upside down in order to get the best angle for Florida's summer time sun.
new possibilities for geothermal
Last year, Obama has sent over $168,000,000 to Florida governments to be used for energy reduction. This program is called EECBG . Each city and county was allocated a percentage of this based on population and was instructed to find a way to spend this money on reducing energy. Each government has to prove that whatever the money got spent on actually reduced energy bills, and was instructed to buy American in the process. Throughout this year, the fruits of this endeavor should be coming to light as construction projects and/or incentive programs. One easy way a local government can gauge the potential for energy savings is to require Energy Star products and systems, of which geothermal is one. This builds upon a program already established by the Department of Energy. http://www.energystar.gov/index.cfm?c=tax_credits.tx_index There are architectural improvements that are listed for federal Energy Star tax credits too. It is worth a visit to this website since there is still time to get federal tax credits for any residential or commercial improvements made in 2009.
