I would like to build a leed platinum building on a shoe string budget? Do you think that it is possible? I am looking to build an 18,000 square foot building on a 9,000 square foot footprint.  Two floors with office space on the second floor and warehouse space on the first floor.I intend to use Solar and geothermal for power and heating. The building will subdivide into 4 tenant spaces. I would like to get a Leed platinum certification. Any ideas on how I can achieve this an a limited budget.

Solar will not work on a shoe string. It will be cheaper the longer you wait. what is your per sq ft budget?

I am an electrical contractor. So we can install it at cost. Add the the rebates and government incentives, solar becomes do-able for us. I am thinking about $16.50 per square foot.

Even you're a well-driller too, "at cost" is still quite substantial for geo, and even more for active-solar. Getting the peak & average loads way down are critical to making it cost-effective.

You get big LEEDs brownie-points by using recycled goods- go with re-cycled insulation for the bulk of the roof/wall/slab (available at significant discounts in quantity from places like the Insulation Depot.) Used goods are something on the order of 25-35% the cost of virgin stock, so doubling the R above code-minimum can still be quite cost effective even with somewhat increased labor costs for installation (repairing dings, foaming in dented corners, etc.)

Using recycled concrete & high fly-ash concrete where-appropriate can also be a big winner. Designing in a lot of cheap thermal mass in the form of recycled concrete can have a substantial impact on peak heating/cooling loads too, and can be utilized to great advantage conjunction with smart systems to pre-cool buildings during off-peak power periods, etc.

Designing in as much passive solar heating & lighting aspects as you can will be far cheaper than any active-solar systems. Designing the building in an integrated fashion iteratively can reduce the size & cost of the mechanical systems required to support the heating/lighting/cooling/ventilation loads while increasing net efficiency. A half-megawatt of active solar thermal to support the heating & cooling loads of a poorly designed building envelope isn't cheap, and it isn't "green", even if it makes quite the visual statement in the aerial view.

You might want to peek at some of the case studies of commercial building retrofits found here:

http://bet.rmi.org/our-work/case-studies/commercial.html

Finding the best balance between building envelope & mechanical system efficiencies is an iterative process. Sizing, locating, & properly specifying the glazing alone can take awhile, but have large impacts on the size & cost of mechanical systems.

I am modeling this building after one that was built by Platt Electric. They have used Solar on their building and they sells back unused power every day, however they have not gone through a winter yet. They told me the cost after rebates was only 7000.00 and they paid for the installation. Their building is the same length as ours and it is 20 feet wider.

The tip on insulation is a good one that I will look into.We plan on building a metal building with a decorative fasade, so the insulation will be very important. Also with using geo-thermal to heat and cool the building, the insulation under the slab could be installed using recycled products.

This building will be located in an area where you can count on the wind blowing almost every day, and I have thought about installing a wind turbine. They seem to be quite expensive though.

I plan to use lots of sky lights  on the upper floor offices and an open floor office plan everywhere except the presidents office, the board room, the managers office and the bathrooms. 

I know a little about concrete , but practically nothing about used concrete. In my limited descussions on this topic, I have been told that used concrete is weak because of the salt we use on our roads in the winter? What does Fly-ash do to concrete.

Thank you so much for your reply

I believe material costs on solar run 60 to 75% of installed the actual electrical work is a small part. It is the least economical depending on were you are located. As Dana said tye building design needs to be synergistic. You need to start with intended use then go to state, federal and utility programs and incentives...

Hi thank you for your reply.
Our intended use will be as office space and warehouse space, 9000 square feet of each, for our electrical contracting business. We live in northern Utah and we recieve about 300 days of sunshine a year. We will use our building only for about 9 hours a day, so the energy use should be fairly low. This building will be at the base of a canyon that gets almost as many windy days.

I plan to capture rain and snow in a cistern and re-use it to water plants. and green space.

I am thinking that we will place photo sensors in the sky lights that will automatically lower the light levels by 4 stages . Full, 2/3, 1/3, off.
Electrically I am pretty well informed of what I can and cannot do. It is the areas of recycled metal studs, floor coverings, ceiling types, building materials, ect... is where i really need consulting.

"...lots of skylights..." can also translate into "...lots of solar gain" if not sized & oriented correctly.  They're pricey on a per square foot basis, but aerogel skylights have a very high R-value and low solar gain, while allowing quite a bit of usable diffuse light and can be a good method of achieving daylighting without degrading the thermal envelope.

Here's the short course on flyash.  I'm sure given the number of coal-fired powerplants in your corner of the world local sources of fly ash will abound, and the prices will be competitive.  A decent concrete engineer could spec the right mix, but fly-ash content in general does good things for concrete.  The folks who made that brochure can probably bird-dog design & supply resources for you (they're in your neighborhood, after all.)  You get green credit for using it since it lowers the portland cement content by replacing it with an industrial byproduct.

Used concrete from roads is probably tough to spec as aggregate in structural apps, but concrete rubble from building demolition may be reasonable.  But even road-rubble in place of gravel/screenings can be used for thermal mass inside the thermal envelope or as drainable backfill.  You get credit for using recycled material, and for keeping demolition rubble out of landfills.

Using concrete in place of other materials wherever possible can add very substantial thermal mass to the building, which improves it's thermal performance.  Where it can/can't be used is part of the design process, but pound for pound concrete has 50% more thermal mass than steel, and it typically takes several times the weight of concrete to achieve the same structural goals with steel. But whether structural or not, the thermal mass benefit is there. (Adding a lot of dead weight to upper floors/roofs increases the structural requirements of your steel building though...)

In a high wind area there may be ways to use that resource to power ventilation systems directly, limiting the use of blowers. That's a much trickier design problem though.  Depending on how much real estate you have to work with, earth-tempering the ventilation air streams might be an option, but if it's tough-digging, fuggedaboudit.   Deep soil temps will vary considerably by altitude (or proximity to hot springs :-) ) in UT, but they're generally ~55F give or take, which tempers peak heating & cooling loads related to ventilation air.  It takes a lot of underground pipe surface area though- it may not fit the budget even with easy-digging.

Speaking of cooling loads-  if you have reasonable access to water, UT is dry enough to take advantage of the best new-skool swamp-cooler technology that doesn't humidify the cooled air stream.  It will knock the socks off of any geothermal based air conditioning system from a total efficiency (and COST) point of view. (Even from a water-use point of view it's on-par with standard air conditioning when you count the water requirements for the higher electricity production.)  Given the locally-cheap sources for natural gas, and dryness of the climate,  going with condensing gas heating + Coolerado(tm) air conditioning will be cheaper up front, with a lower carbon-footprint than (UT's coal-fired) electricity-powered geothermal. 

For a chunk more money you could heat the units hydronically with net-metered micro-cogenerators (eg:  http://www.marathonengine.com/intro_eco.html# but there are a handful of others) and thermal storage buffer tanks to buy a bunch of brownie points, but that's probably not going to fit a shoestring budget.  Properly implemented you can get 90%+ fuel use out of space-heating cogens, 20-30% of the output being in the form of electricity to the grid, the remainder being thermal.  This is compared to the typical ~ 25-35% thermal efficiency out of a coal-fired power plant measured at the electrical load. (You'd need an average COP of 3.5 or more on your geo to pull ahead of a cogen for raw thermal efficiency, and an average COP of 7+ to beat a gas-fired cogen with coal-fired geo on carbon footprint.)  I'm not sure what that buys you in LEEDS points, but it should count for something.

cogens work great if you have a place to use the heat all the time, as in restaurants, hotels,central plants, manufacturing, etc where the heat and electrical output can be use simultaneously.In this application a condensing boiler could be designed with less than 100* supply temp that would put the efficiency around 98%. I would look at a triangle tube prestige using 1 boiler and meter heat to the tenants. Your heat load could be under 10 btu sq ft. I have little experience with swamp coolers in the midwest but I have read the latest generation are much improved in controlling humidity and can be incorporated into a central system.

Humidity is not a problem in Utah, However in the winter we need to humidify the air because it is so dry. Swamp coolers do work well here. I agree that co generators will produce to much heat.

One of the reasons that I was looking at Geothermal heating and cooling is because a developer just up the street started to build a 5 story building and uncovered a natural spring square in the middle of their building. They shut down the construction for a little over a year and used the spring's geothermal energy to heat and cool the building. and my understanding is that they are experiencing some real substantial money savings. It sounds like most of you think that this not the way to go, especially on a limited budget? Thanks for your comments.

Depends on building use, load, design..local utility rates, local and state incentives....As with any technology it has to be properly applied to get good results...If u have cheap electricity and are happy with the carbon quantity then it may very well be the best for your application...I would look hard at the true installed cost of solar, wind, and geo before installing any of them...Dana do you have any links for lifecycle cost comparisons.

Platinum will be a challenge.  If you haven't done it, look at these documents:

LEED 2009 NC http://www.usgbc.org/ShowFile.aspx?DocumentID=7244

LEED 2009 NC Checklist http://www.usgbc.org/ShowFile.aspx?DocumentID=5719

Check your site points carefully.  You will need a lot of them to achieve Platinum.  You can achieve a lot of points with technical solutions, but there are some Site points that are hard to achieve.

You also need a LEED AP to help you through the process.

Bruce

I already have a Leed AP firm working on the project. And I totally believe that Leed Platinum can be achieved. My concern is can it be afford-ably achieved on a limited budget. I believe that most business owners view it as an expensive dream. If green building design really wants to get totally integrated with modern business than it has to fit into peoples budget. I believe that anyone can build a Leed Platinum building if you are willing to throw enough money at it, but if we are really serious about making full use of our resources then we need to think through our technology for the most cost effective solutions. This is what I am attempting to achieve. I need a new building. I believe in green technology. I am not a rich businessman. I am looking for the best solution for my situation.

Let me give you a little information about the site. It is a 3/4 acre triangle shaped site. It was an old farm with a greenhouse that was crudely torn down and then abandoned by the previous owner. It is adjacent a main highway, with express and regular buss service. This city has no sewer system. This city in in bad need of income. It has very little business base. It has a natural stream adjacent to the property. It currently is a safety hazard for the residents, due to the abandoned rubble filled pits left by the previous owners. There is so much wind in the area that the trees are growing sideways.

I am also working on a Green MBA, and I am considering this topic as a guide for my thesis.

Thanks for the Info Bruce.

Posted By William Hickman on 18 Aug 2010 08:11 PM
Humidity is not a problem in Utah, However in the winter we need to humidify the air because it is so dry. Swamp coolers do work well here. I agree that co generators will produce to much heat.

One of the reasons that I was looking at Geothermal heating and cooling is because a developer just up the street started to build a 5 story building and uncovered a natural spring square in the middle of their building. They shut down the construction for a little over a year and used the spring's geothermal energy to heat and cool the building. and my understanding is that they are experiencing some real substantial money savings. It sounds like most of you think that this not the way to go, especially on a limited budget? Thanks for your comments.

There are many thin spots in the Yellowstone caldera, and if the water temps of a hot or tepid spring are high enough the COP of the geo heat pumps soar in heating mode.  (If it's over 90F it may be useable without heat pumps in a well-insulated building by going with radiant floors/ceilings for heat distribution.)

Cogenerators only produce too much heat if the control is set up to regulate the electrical power output, not the thermal output. Micro-cogens are usually set up to satisfy the thermal demand, not the electrical power demand, since building scale electrical loads vary more quickly and with a wider range than a single system can optimally run.  Thermal loads change more slowly and are more predictble.  At low load conditions, designing in thermal buffer tanks to guarantee minimum run-times optimizes the overall efficiency.  They're almost always under-sized for the peak heat load, but if sized for something like the wintertime average heat load the duty cycles & total output are pretty good.

The cogen portion of the Freewatt  systems for residential use put out well-under a typical N.American home's heat load  (only ~12KBTU/hr) , but can run nearly a 100% duty cycle for 3-4 months out of the year with only 50gallon HW tank as buffer to keep it from short-cycling.   Bigger micro-cogen systems for buildings like this have to be custom-designed  and buffers sized for the purpose, but 5-10kw (electric output) units are modular/scalable for larger thermal loads.  The tiny Marathons I linked to at max-modulation only deliver 13.8kw (~47KBTU/h) thermal, which is well under the peak heating loads of many larger single-family homes.  Even if well-insulated & optimized for passive solar, the average December-March heating load of a building your size will be in the modulation range of one (or multiples) of those.  (I was thinking about 4- one per rentable space might be appropriate.)  The peak thermal loads can be handled by (reduced size) condensing gas boilers/furnaces.  It's likely that one Freewatt system-per unit would work as well, but custom designs are more flexible and would deliver higher net electrical output- the Freewatt was really designed for residential apps. (For the record, one of my co-workers is a well-satisfied customer of theirs, but the thermal output of their hydronic systems are ridiculously high for my home due to the oversizing of the boiler they've married it to.)

Payback on a micro-cogens is typically much faster than PV-solar at current levels of solar subsidy, but do the math carefully- YMMV.

The 8-ton Coolerado systems are likely to be a modular-application too- you'll likely need at least 4, and maybe as many as 8 depending on required ventilation rates and the actual cooling load.

Whats the point of a cogen if it is less efficient than a condensing gas boiler that is much cheaper to install Unless you are peak shaving.

Posted By ilgeo on 19 Aug 2010 02:48 PM
Whats the point of a cogen if it is less efficient than a condensing gas boiler that is much cheaper to install Unless you are peak shaving.

The point is that it's far MORE efficient than a thermal powerplant that sends "waste heat" up the cooling stacks, and suffers another 6-8% of losses as heat in the windings & transformer cores of the distribution grid. The premium output lof the cogen is the electrical power, which (in most cases) will be produced at far below the combined-cost of  retail electricity + space heating.  You can't offset your electric bill with a mod-con boiler at any efficiency.

The net-effect on carbon footprint is profound, since the local grid in UT is predominantly coal-fired, whereas the cogen is natural gas, with only ~ 45% of the atmospheric carbon output per BTU, and the net-efficiency from an electrical generation point of view to the first transformer can be considered 95-100%, not ~30%, since the bulk of the remaining source-fuel BTUs going to the building, not cooling towers, and most of the power will be used within 1-transformer's reach of the generator at near-zero distribution loss.  Strictly as a generator it would only have ~25% thermal efficiency (slightly lower than a fossil-fired power plant's ~30% net grid efficiency), but in any reasonable cogen system design less than 10% of the source fuel's energy is going up the stack. Viewed strictly as a space heater it's only ~70-75% efficient, but if you have a use for the electrical output (or it's net-metered) it's a total win.

If you take one of the micro-Marathon's and run it at it's max output for 3 months out of the year and average 50% for another 4 months of shoulder season it's producing ~17000kwh/year, while producing ~75% of heat benefit you'd get out of a mod-con burning the same fuel.  You have to do the math on the difference of the heating-fuel cost delta against the value of the offset electricity, but in most markets it's a very strong win, (even though it's a loser if viewed as either a heater or a generator alone.)

FWIW (probably not showing up in UT any time soon, but...) in Germany there's a utility using distributed cogens as means of stabilizing the grid to be able to use a greater share of intermittent renewables (notably wind) in the generation mix.  In those systems both the generators and the buffers are over-sized for the local thermal & electrical loads to give the utility operator some flexibilty to run the cogens even when the immediate thermal demands are low.  The cogens are controlled and maintained by the utility, not the building owner, but the utility guarantees to meet the thermal demands of the building owner, and the building owner's power bill basically goes away (unless they're ULTRA powerhogs, and actually use more power than the 10s of kilowatts the VW-powered cogens deliver.)  Zie:  http://www.lichtblick.de/uf/pdf/091...ftwerk.pdf  und http://www.lichtblick.de/h/technik_291.php  und http://lichtblick.de/h/Ueberblick_286.php 

Play the vidi, even if your German is lousy- the gist of the overview is clear from the graphics.  They're on track to have a nuke's-worth of highly flexible networked cogens in place over the next half decade.  The model works for them, than in warmer parts of the US, since they don't have a significant air-conditioning season, and peak seasonal loads on the grid are reasonably correlated to heating loads. But that's not to say micro-cogen sized for the winter-average heat load wouldn't be a net win in northern UT.

BTW: The installed cost of the Freewatt hot air cogen package is comparable to that of a condensing hydronic boiler, and the system design time is much simplified compared to a fully customized cogenerator. It's electrical output of the tiny 1-lung Honda they use is only about 1/4 that of the Marathon's, and it's efficiency as a generator is only about 80% that of the Marathon's. In a commercial app the Marathon is probably a better match.


...and...

If you also went ahead and did a ~8kw photovoltaic array it would somewhat level-out total power output from the building's resources over a year- the cogen's peak output occurring December-February, and the PV array peaking May-July. But again, a serious PV array is not usually within a shoestring budget unless the subsidies are very rich indeed.

yes it may be around the same cost if you only need 12k btu but I dont think that will get to far in an 18000 sq ft building. I just dont see the point of a cogen in this types of applications.

Posted By ilgeo on 20 Aug 2010 12:40 AM
yes it may be around the same cost if you only need 12k btu but I dont think that will get to far in an 18000 sq ft building. I just dont see the point of a cogen in this types of applications.

The output of the condensing hot air furnace(s) they married the Freewatt cogen to can be an order of magnitude higher than the thermal output of the Honda, and is included in the installed price.  I agree the Freewatt is probably not a good match for a commercial installation-  and the 1.2kw electrical output is also well-under average load of even most light-duty offices that might take 1/4 of the building.  Systems built around Marathons & others would be far more appropriate & more flexible than the tiny Honda.

Unless there are compelling reasons to do so, I'd assume the heating systems would be separate for each of the 4 leaseable units envisioned, so we're really only talking about supporting the thermal load of something like 1/4 of the 18000', which may be quite modest in a well-designed building in this location.  Way more than 12MBH, but not likely more than 3x the thermal output of the Marathon.  If it is, there are other small cogens out there with more appropriate thermal output.

To see the point, maybe you need to do the math on a real installation.  But the benefits are usually quite substantial, and usually need no subsidy to be a good to excellent investment in most electricity markets in heating dominated climates of over 4000HDD. There are several factors to optimizing it though- sizing of the cogen to the thermal load is key, as well as the base electricity load & price, and the net-metering terms.  In high-priced electricity markets (as in much of the NE), it can become a no-brainer type of investment, NPV+ in a 5 year analysis.  In my biz-partner's residence the hydronic version of the Freewatt system was NPV+ in ~2.5-3 years, but he's in 20cent/kwh-land, and is allowed to net-meter at retail. His retail NG prices are also high too though- north of $1.50/therm even after the price crash.  YMMV.  In UT the prices of both electricity and natural gas are around half what they are here, which WILL affect the financial analysis.

The point  of cogens relative to net carbon emissions for supporting the combined electrical & thermal loads of the building are pretty straight-ahead, when located on a primarily coal-fired section of power grid.  What that buys you in LEEDS points is beyond me however.

A bigger issue in this case might be finding the right engineers to design the systems properly if it's going to be a full-custom design.  (The Freewatt systems are pre-engineered for a residential application and fairly straightforward to spec, but that's a very different market.)

Sorry Some how I posted this twice. to long in the sun this afternoon...getting soft...Point me to some good reference material and I promise to read it...Maybe I'm operating under false assumptions and I do admit that micro gens make sense for the grid ..Eric