Comment Here! LEED v4 Energy Stringency Update

I have three comments related to the proposed updates for LEED for Homes and LEED for Homes Midrise:

1) for EA Annual Energy Use, within the Midrise pathway, I like the change to the home size credit piece. The current design (in V4) awards too many points for small dwelling units, and I believe that removes the incentive for many projects to pursue greater energy savings. My recommendation would be to also adjust the home size credit piece for single-family and low-rise buildings.

2) I applaud the increased performance requirements that come with this update for midrise buildings, but I'm disappointed to see that there were no increases in the requirements (for either the prerequisite or credit) for single-family and low-rise buildings. The current design (in V4) is somewhat easy for single-family and low-rise buildings, so leaving the requirements for those building types untouched seems like an oversight. I'd like to see the prerequisite changed so all single-family/low-rise projects must meet a HERS Index below 70 (perhaps 66 or 68), and the LEED Energy Budget pathway should also be made more stringent. There has been increased volatility in how the Target Index is calculated, and reference to the Target Index should be removed altogether. 

3) The Greenhouse Gas metric, in conjunction with ASHRAE Std. 90.1-2010, may produce some unintended consequences. I've analyzed various project models using the GHG method and in markets with very clean electricity (e.g. Seattle, California, Quebec) it will be possible for projects to meet the prerequisite and earn points using the GHG metric *while failing to meet ASHRAE Std. 90.1-2010*. For example, it's quite common for residential projects to earn 30-50% savings in the domestic hot water end use. If a project with a very clean electricity source installs a gas-fired water heating system, the savings rate under the GHG metric are driven almost entirely by the natural gas savings (because the GHG impact of the electricity is nearly zero). This means a project in a market with clean electricity could install electric resistance heating, have a bad envelope, bad lighting, etc. and as long as the savings in the gas-fired DHW end use is good, the project will do well under the GHG metric. This is not a theoretical point; I've already seen projects that fit this profile that have used EApc95 to earn points despite a fairly poor performing building. I recommend that the prerequisite be changed so all projects must at least demonstrate 5% cost savings - this would prevent any situation where a project could perform worse than the current V4 requirement. 

Comment #1:

Establish an energy performance target no later than the schematic design phase. The target must be established as kBtu per square foot-year (kW per square meter-year) of source energy use.

kBtu/sf and kW/sq.m. are not equivalent units. One is energy and one is electric demand.

Comment #2:

The point thresholds for cost and source energy should be put into separate tables at a minimum. The wide range of source to site electric factors as well as utility costs means certain projects see 50% source to site savings but only 15% cost savings when following Appendix G.

Comment #3:

Please provide some clarification around on site renewables with regards to the metering configuration. For on site renewable energy that is in front of the meter, projects should not be able to claim the savings towards their building unless the power is specifically purchased and has an ownership/lease agreement structure which allows for such configuration. Behind the meter systems are more straightforward and should be counted as they will be a net meter. Another item that is not clear is around excess produced renewable energy that is not consumed on site and is fed to the grid. Depending on the locale, this electricity or energy may be priced differently or worth more in terms of carbon emissions than what the building pays for the same energy.

Comment #4

It appears that the prescriptive path option will no longer be available after this update? The removal of a prescriptive path - especially for prereq compliance - seems inappropriate for ID+C where we regularly see projects that can't meet the current prereq via modeling due to limited control over existing base building systems, typically when there are a mix of fuel/electric systems serving the project. These tenant projects should continue to have a path to being rewarded for optimizing the systems within their control, such as LPD, lighting controls, plug loads, and ES equipment. Additionally, this change threatens to have a significant negative impact on smaller ID+C projects that don't have the budget for modeling and don't stand to benefit from the system-design outcomes that a project would if it were specifying full systems of new equipment - This may cause smaller ID+C projects to elect not to pursue LEED at all, due to added costs and difficulty complying.

Comment #5

Disagree with the basic premise of altering performance thresholds within the 'v4 update' as this sends a confusing message about what it means for projects to be 'LEED v4' certified. How can we have some projects that met v4 LEED previously with 3% energy savings or even no energy modeling, and now tell projects it is a minimum of 6% for the same certification? How can these different achievements be recognized? Raising the bar that projects need to hurdle should only come with new versions of LEED and updates within an existing version should primarily seek to clarify language and remove unnecessary obstacles for complying with the existing criteria. More stringent energy performance requirements are welcomed for the forthcoming v5 LEED but v4 would better be targeted for sunsetting rather than reworked.

Hi.

Compliance with the mandatory provisions of ANSI/ASHRAE/IESNA Standard 90.1–2010 has been in this prerequisite for a long time, but does not meet reality for projects outside the US. I'm aware that we have USGBC-approved equivalent standard for projects outside the U.S.) added to the requirement language, but as the regulations in other countries are usually different, equivalency is very hard to prove.
In addition to inumerous references of US standards, ASHRAE 90.1 mandatory requirements include items that make construction and maintenance more expensive. 
My suggestion would be making the mandatory provisions included in the baseline model only. The design model should comply with the actual legal and engineering requirements of the country or region it is being buit at.

I made a redline copy of the prereq and credit, sharing here to help others dive in :) This does not include the points table or the v4 prescriptive options that got removed.