Intent:
- Increase on-site renewable energy self supply
- Reduce environmental and economic impacts associated with fossil fuel use
- Offset building energy costs
Implementation:
- ELIGIBLE TYPES OF RENEWABLE ENERGY:
- Solar
- Photo-voltaic
- Wind
- Geothermal heating and electric
- Biomass
- Bio-gas
- Low-Impact Hydro Electric
- NON-ELIGIBLE TYPES OF RENEWABLE ENERGY:
- Architectural features
- Passive solar
- daylighting
- geo-exchange (ground source heat pumps)
- green-power from off site
- To gain points: achieve savings in building annual energy savings cost
- 2.5% = 1 point
- 7.5% = 2 points
- 12.5% = 3 points (max)
Codes:
- DOE (Department of Energy)
- CBECS (Commercial Building Energy Consumption Survey)
Submittal Phase:
- design
Extra Credit:
- Gain 1 additional point for 17.5% through exemplary performance. (4 total)
More Energy & Atmosphere Credits
- EA P1 – Fundamental Commissioning of the Building Energy Systems (prerequisite)
- EA P2 – Minimum Energy Performance (prerequisite)
- EA P3 – Fundamental Refrigerant Management (prerequisite)
- EA 1 – Optimize Energy Performance
- EA 2 – On-Site Renewable Energy
- EA 3 – Enhanced Commissioning
- EA 4 – Enhanced Refrigerant Management
- EA 5 – Measurement & Verification
- EA 6 – Green Power
47 Comments On This Post
Okay, another question…isn’t there an extra ID credit available for EA-2 if building energy savings reaches 17.5%?
Tim,
I don’t believe so – 12.5% is the highest percentage threshold here as far as I know. Where are you getting this number from? Are you looking at the 1st edition of the reference guide or the second edition? I know there are a few minor differences such as these between the two.
Pat-
Looking in the 3rd edition page, 208 it states that 17.5% or more can earn a project an ID point.
Thanks-
Deanna
Test day May 2
I believe Deanna is correct and am also using the latest edition of the NCv2.2 Reference Guide to study.
By the way, your website is extremely helpful – thank you!
What do we need to be able to know or understand about the calculations for this credit for the exam?
Thanks,
Gary
For this particular credit, just know the percentages and how many points each one is worth. Don’t forget about the examplary performance option too!
Nothing else calculation wise for this particular credit.
Good luck!
Thanks Pat!
Gary
I am confused regarding the method used to calculate the Annual Energy Cost in the simulation model (EAc1). However, this is my question:
Is the fraction of the energy cost supplied by the renewable sources deducted from the Total Energy Cost of the Building?
FY: Be sure to remember tidal/wave power as acceptable forms of renewables–I’ve had two practice test questions now with this.
I have same question as Giovanni. Can the energy cost provided by renewable source offset energy cost calculated in EAC1 calculations?
do back-up generators count into “on-site renewable” if they’re using the appropriate fuel type?
I would think that by definition a “back-up” generator is not used to offset a building’s annual energy costs, which is the purpose of on-site renewable energy systems. Rather it is used for unexpected power outages.
Gary
What to renewable energy credits have to do with EA 2?
Is this this what you get with net metering?
I have a question on the extra credit, I am using the PPI Everything you need to know about LEED, and it says that you can get an ID credit if energy production is 17.5% of annual costs…Is this right?
uh…I just saw the extra credit section at the end of the page…Thanks! This website is AWESOME!
so can someone explain this?
22. Using rooftop photovoltaic panels supplying 17.5% of a building’s energy needs
would help a project comply with EA Credit 2, On-Site Renewable Energy, and
which other credit?
A) ___ ID Credit 1, Innovation in Design, for exemplary performance under
EA Credit 2
B) ___ EA Credit 1, Optimize Energy Performance
C) ___ EA Credit 6, Green Power
D) ___ SS Credit 7, Heat Island Effect
why is the answer not a? it is 17.5 which gives the extra credit point, but the answer is b, I get where the b comes from, just wondering why it cant be a
Asma,
17.5% is building’s energy not the cost. That is why A is wrong.
thanks
Grass and asma, I was confused as well by that one. Thanks for pointing out the “needs”, not “costs” in that sample question. However, isn’t EAc1 also based on costs, not needs? Why would B be the correct answer?
Yes, I am still confused about the difference between cost and needs in EAc1 and EAc2. As I understand, EAc2 is just dealing with offsetting energy cost, whereas EAc1 is strictly energy performance against the baseline ( but you must include costs?) .. oh boy confusing..
also, this site is truly wonderful, it has helped me so much, thank you!
A sample question:
Responsibilities for LEED-NC documentation are commonly divided among the design and construction team during the design development phase. The mechanical engineer is typically responsible for providing documentation for which of the following credits? (Choose two.)
a. EQ P1 Minimum IAQ Performance
b. EQ 1 O/A delivery monitoring
c. EQ 4 Low-Emitting materials
d. EA 2 On-site renewable energy
e. EA 4 Enhanced Refrigerant Management
The answer is b and e. I am OK with b and e, but why isn’t d correct?
A mechanical engineer is the only decision maker for b (EQ 1), d (EA 2), and e (EA 4) in Design Submittal phase.
Could someone please provide your input? Thanks.
Richard, I guessed d as well, but when I rethink it, it seems that you could say that you don’t need a mechanical engineer to let you know how much energy is being used on the project and how much energy the on-site renewable energy saves. You’d want the electrical engineer and the renewable energy rep for help with that.
The refrigerant, on the other hand, is almost all Mech guy’s domain.
building green sample test, #63
In order to ensure continuous operation of the assembly line, a manufacturing facility in Oregon seeking LEED certification installs backup generators powered by corn-based biodiesel, with capacity to provide 50% of the facility’s electricity needs. Accding to EPA’s Emissions & Generation Resource Integrated Database, an average of 60% of the facility;s utility electricty comes for hydroelectric generation. The facility is eligible for how many points in EAc2, On-site Renewable Energy?
A.0
b.1
C.2
D.3
Answer is A. Is that becasue they say it talks about 60% of the elecricity rather than the actual cost %?
Joy,
The calculation for EA 2 should be based on EA 1’s simulation (Building Performance Rating Method) or, in not performed, DOE’s EIA 2003 Commercial Sector Average Energy Costs by State, in conjunction with the CBECS.
Another thought, is hydroelectric generation eligible for EA on-site renewable energy. I cannot tell from page 204, Reference Guide.
Anyone has other input?
According to the reference guide only “low impact hydro electric power systems” are eligible, the ques. doesn’t say low impact..may be thats why answer is 0.
Any other thoughts?
Hydroelectric generation of electricty is covered under Green Power EAC6, which means that it is not generated on-site as per LEED Ref guide. EAC2 only focusses on on-site renewable energy. Please correct me if I am wrong.
Thanks!!
This was a practice exam question… wouldn’t it be D because of exemplary performance??
A project team in southern Utah is implementing an on-site renewable energy plan that will offset normal building energy costs by 17.5%. How many points would this project earn under EA Credit 2, On-Site Renewable Energy?
A-1 point
B- 2 points
C- 3 points
D- 4 points
E- 5 points
Solution:
The maximum number of points that can be awarded to a project for EA Credit 2, On-Site Renewable Energy, is three points. One point is awarded for 2.5% savings off the building annual energy cost, two points for 7.5% savings, and three points for 12.5% or greater savings. With energy cost savings of 17.5%, this project team qualifies for three points.
The answer is C.
regarding the building green sample test, #63,
the answer is A, because “corn-based biodiesel” isn’t renewable energy.
Hrm, well im going to have to trust pat on this one because I dont have the third edition of Leed nc2.2. The answer should be D because they added the exemplary option in the latest edition. I would bet this is an old test question. Where did it come from?
It came from PPI Exam Cafe… i hope those are good practice exams to use because I am taking it very soon. =/
Hi, Sun:
Could you please let me know where in the Reference Guide I can find the info about “corn-based biodiesel?” Thanks.
Hey Jana,
The answer to your question is C because you can earn max. 3 points under EAc2, the exemplary point earned will be counted under IDc1. Hope this helps.
Ah thanks, youre right.. I got caught up because I know they added the 17.5 recently so I didn’t know if it was an old question..makes sense tho!
I believe mamz got the right explanation to Jana’s question. 3 points is the maximum, and extra 1 point can be earned for exemplary performance under ID 1.
A total of 4 points = 3 points under EA 2 and 1 point under ID 1.
Ah, that makes sense. Tricky tricky
Getting back to Joy’s question above. I don’t think the reason for the answer being “A” has anything to do with corn-based biodiesel being renewable or not – (I happen to think it is)- anyone else, please feel free to weigh in on this.
The important distinction about EAc2 Renewable Energy is that it is calculated based on percentage of energy COST and the question refers to energy USE or “NEEDS”. LEED distinguishes between cost and use for this credit. Interestingly, EAc4, Green Power, IS based on energy energy USE, instead of cost. Tricky!
I’m still a little confused on this geothermal and geo-exchange issue.
For the purposes of the LEED exam, are geothermal pumps deal breakers?
I see in the reference guide that anything that involves the following is not eligible:
– ‘ground-source’ heat pumps,
– energy from the earth’s surface and
– vapor compression
However, how are you supposed to get the deep earth source energy that LEED allows out of the ground without pumps? Does LEED distinguish between ‘ground-source’ heat pumps and other kinds of geothermal pumps? Any thoughts on this?
Julia:
First of all geothermal systems come in different forms and have different applications.
For LEED, eligible geothermal systems are those that utilize DEEP earth water or steam to GENERATE electricity.
The most obvious examples would include systems that have deep wells drilled into the earth to harness the power of steam to turn turbines thus creating electricity.
A not so obvious example would be using deep earth hot water to initiate boiling of liquids with a lower boiling point than water. This creates steam, which turns turbines and creates electricity yay.
Another example would be pumping water down into the earth so that it boils and creates steam and turns a turbine and creates electricity. Seeing a pattern yet?
Another eligible system could utilize hot water closer to the surface to help with heating a building.
Now lets talk about what the USGBC will not allow as eligible for eac2; GEOEXCHANGE systems that use heat pumps. Geoexchange isn’t technically geothermal energy because most of the thermal energy generated doesnt actually come from the earth. These systems will usually have a network of pipes just beneath the ground. A liquid will pass through these pipes and underground and heat exchange will take place (ie. if the liquid is colder than the earth than it will absorb heat energy, if the liquid is warmer than the earth the earth will absorb the heat and cool down the liquid… equilibrium at work here).
These network of pipes however are part of a vapor compression system which does most of the heat transfer.
Without getting into too many details, a geoexchange system uses the liquid in our underground piping to change the state of the refrigerant gas in a heatpump (after the refrigerant has been compressed). The water then carries the resulting heat energy away. In the mean time the refrigerant is reduced in pressure which reduces its temperature and passed into an evaporator where it removes heat from the warm air circulating through the system. The refrigerant evaporates and gets compressed again and the cycle repeats. As you can see, the refrigeration cycle is what is really doing all of the work.
So when you think pumps, think heat pumps and vapor compression. These will not be eligible because they don’t serve the intent of the credit well.
Thanks for everyone’s input on that question of mine.
I passed today with a score of 190!! Good luck to everyone else who will be taking the test!
Joy
Sample ques:
Which one of the following might contribute to earning EAc2 Renewable energy?
a. solar thermal panels as means of heating water.
b. a bio-gas fueled generator as an onsite source of electricity.
Answer says b, but I wonder why not a?
Mamz,
I think its B, because A deals with the solar energy heating the water, not offsetting building energy costs. Though it does reduce energy costs, I think it is too indirect to county.
Mamz,
I think “solar thermal for heating water” is considered passive solar, which is not eligible for EA 2. (see pages 204 and 168, Reference Guide).
EA Credit 2 On-Site Renewable Energy can earn an innovation point when the %
of renewable energy is 17.5% or greater (see reference guide errata, this is
not in some versions of the reference guide)
is this true? i found this explaination while giving a practice test..and i couldnt find any errata sheet which says something like this!
SOS!
Akanksha – the answer is yes. But refer back to the thread starting on Feb 14 to be sure you know when and how it is applied.
Akansha,
Check page 9, EA 2, of the LEED NC 2.2 errata sheet at http://www.usgbc.org/showfile.aspx?documentid=3335
Why WIND is eligible and , Daylighting is not eligible. could you please tell me , On what reason they have divided this in to 2 catagerous.
Interesting topic, but if you need more info on conserving energy and not wasting so much of it. check this blog