Operations: Live monitoring of electricity use works

Since Earth Day, I’ve been following Energy Circle’s energy monitoring experiment. With the combined resources of a household electricity monitor and Twitter (plus an assist from some Google-fied graphics) they are nearly 90 days into a fascinating experiment.

With a reasonable passage of time, it was appropriate to provide an update. In this case, Energy Circle advocates that real-time monitoring works (24 hours later doesn’t).

You really should follow through for the full story, but here are the main reasons:

1. Spikes Hurt.
2. Baseload Matters.
3. Our house has a heart beat.
4. Humans screw up.
5. The right tools are critical.
6. Data=Action.
7. Some bulbs really cost you.
8. Efficiency is a family matter.
9. The little shifts count.
10. Real-time leads to a real map of action.

Energy Star Fades as Efficiency Rating – WSJ.com

The Wall Street Journal reports that the EPA is upgrading the residential Energy Star ratings, which currently require a home to achieve 15% greater efficiencies than model building-efficiency guidelines.

Perhaps embarrassed by the thought that homes 57% larger than the national average still receive Energy Star designations, the EPA’s actual motivation seems to be driven in part by technology and in part by a desire to reduce the number of Energy Star rated homes built.

Residential energy efficiency is rapidly evolving in the U.S. 10-20% of states have adopted or are studying the adoption of energy codes more stringent than the 2006 IECC, and many significant new requirements were adopted in the 2009 IECC. Furthermore, the current over-supply of housing stock in the marketplace reinforces the need for ENERGY STAR qualified homes to stand out from the competition. EPA is developing new guidelines to help ensure that ENERGY STAR continues to deliver homes that are high-quality and meaningfully more efficient than standard new construction. More rigorous guidelines will strengthen the integrity and value of the ENERGY STAR label, thereby increasing the success of raters’ and builders’ partnerships with ENERGY STAR.
(Source: Energy Star 2011 FAQ)

In the Fact Sheet, issued May 4, 2009, EPA went with the simpler to explain bullet points:

EPA believes that the next generation is an opportunity to:
• Add requirements that ensure a comprehensive approach to building science
• Ensure high‐efficiency equipment and products in qualified homes
• Add new, high‐value on‐site inspections to ensure that ENERGY STAR qualified homes perform to expected
levels
• Limit the carbon footprint of large homes earning the ENERGY STAR

(Source: Energy Star Qualified Homes 2011 Fact Sheet)

The short version of the upgrades are that new requirements focused on both whole building design and minimally intrusive efficiency selections will be incorporated into the guidelines. These include guidance on thermal, air, and moisture flow; an integrated HVAC system; efficient appliances; more efficient water distribution (low flow aerators); and higher efficiency hurdles for larger homes.

EPA estimates that the proposed changes will add about $4300 to the cost of a home, or $23/month in additional mortgage burdens. It estimates monthly energy savings of approximately $37/month. The financial estimates are well summarized in this 20-page PDF.

You can view all of the changes at the EPA’s Energy Star Qualified Homes website. The public comment period ends July 10, 2009.

Better Homes: We can rebuild them. We have the technology.

A couple of articles came on construction techniques came across the transom in the latest issues of Builder and EcoHome magazines.

The first article summarizes the traditional with a twist methods used by FirstCoast Homes to achieve Energy Star-ratings for all of its starter and move-up homes. Their efforts combine design, construction technique, and appropriate appliance upgrades, which limit the total cost to an estimated $1,000 per home.

[Note: As always, I try to bring additional value via hyperlinks. Take a look at all of them for additional information]

The 5 ways revealed to Builder:
1. Improve upon traditional methods through proper installation and 3rd party evaluation of various systems. Be sure to read this ode to traditional techniques from the February 2008 edition of EcoHome.
2. Build a tighter envelope through foam sealing penetrations, caulking baseplates, and use low-expansion foam around portals. These techniques and more reduce potential air intrusion “by about 30%,” according to FirstCoast. Duct blaster and blower tests ensure that the building is tight before the irreversible work begins. (Johns Manville believes 5-25% of ducted air is lost through leakage.)
3. Correctly install the right insulation by using a mix of foam around penetrations and fiberglass elsewhere. Make sure contractors install it right and protect it from crushing, moisture, and other damage during buildout.
4. True value engineering identifies areas to spend smarter, not just less. By reducing the number of windows, FirstCoast reduces the direct cost of windows, but also the size of the HVAC system, saving an additional $400-800 per house.
5. Identify other revenue sources by working with utility companies, and government incentives to reduce the cost of homes, appliances, and testing.

At sister publication EcoHome, green building consultant Mark LaLiberte highlights 5 common errors made in all construction:
1. HVAC ducting through unconditioned space needlessly reduces the effectiveness of your heating and cooling system. Put the ducts in soffits or between floors to maintain their ambient temperature. Research from WSU provides great detail on HVAC in conditioned spaces.
2. Tightened envelopes without intentional ventilation can cause stale air, odors, or moisture to accumulate. Install a whole house ventilation system to bring about 50CFM of fresh air 3-4 times per hour.
3. Improper flashing and drainage leads to moisture buildup and reduces the effectiveness of insulation and moisture barriers. Multifamily folks know all to well the hazards of moisture and mold growth, so this should be well-trod ground. For additional information, Freddie Mac offers a Moisture Management Plan to help identify sources of moisture build up.
4. Poorly installed/selected installation reduces energy efficiency and adds to costs (see above). Exposing it to moisture during the installation process can cause a cascade of additional systemic failures. Watch out for improperly insulated thermal bridges, particularly metal studs that have contact with exterior surfaces. This can be an unfortunate method of reducing the effectiveness of your HVAC system.
5. Excess waste leads to excess costs and can be offset by better reuse of construction materials but more importantly through increased standardization of all materials. All systems have a ‘commodity size’ and making use of these common measurements reduces the potential for waste and on the interior, unsightly seams.

EERE Webcast December 17th on State Green Incentives

The Department of Energy’s Technical Assistance Program will present “State Policies to Encourage Green Building Principles” via webinar on December 17th from 3-4.15pm EST.

Presenters for this series are:

Brian Lips, a policy analyst for the North Carolina Solar Center at N.C. State University and conductor of research related to the Database of State Incentives for Renewables & Efficiency (DSIRE). He will give an overview of state green government policies nationwide.

Chuck Sathrum, program manager at the North Carolina State Energy Office will discuss the N.C. Utility Savings Initiative, a comprehensive program to reduce utility expenditures and resource use in public buildings.

Angie Fyfe: Fyfe, manager of the Greening Government Program at the Colorado Governor’s Energy Office, who will discuss how executive orders encourage state employees to reduce energy consumption.

Background material can be found in the Energy Office Project Briefs.

Past webinars covered energy efficiency in data centers, solar PV financing, energy efficiency in improving air quality, and several state-level initiatives.

Renewing focus on the low hanging fruit

Green Building Law wrote a good post promoting pink over green (i.e. insulation over solar photovoltaic systems). Similarly, CSM ran an opinion piece entitled “Green homes: solar vs. energy efficiency” that came to a similar conclusion. GBL (and I) agree that CSM didn’t seem to try very hard in their search for solutions, writing that “Policymakers say energy efficiency doesn’t have out-of-the-box solutions that are easy to mandate or incentivize.”

Regular readers may recall that this site discussed weatherstripping just a few weeks ago as part of an ongoing discussion of complexity-free solutions.

The current incentive structure, while it has the added benefit of promoting R&D and other desirable benefits, typically sells short more reliable and well-known solutions that could be installed by soon to be displaced skilled but non-professional tradespeople. Single family home energy audits cost several hundred dollars ($400-700 seems to be the going rate in the DC area) but per unit costs would be significantly less and could actually be performed by on-site service teams. So long as there is a difference between interior and exterior temperatures, using an infra-red imager will allow you to see cold spots and intrusions without a blower door. I can do it and I’m about the most unskilled person allowed on sites.

My firm has investments in about 230,000 units nationwide in a little over 2,100 apartment communities. Because most of our projects participate in the LIHTC program, we are subject to the QAP process, in which states mandate certain minimums to receive tax credits for affordable housing. If these requirements (occasionally incentives) could be included in market-rate housing, the impact would be both immediate and widespread. To put that 230,000 unit number into perspective, there are 5 states with fewer than 260,000 households (2000 Census).

The way to improve efficiency is to educate owners and lenders, and use effective policy tools to promote the best comprise of timing, cost, and achievement. Eventually, home inspections will automatically include an energy audit. It is up to policy makers and lenders to speed that date.

PD&R Periodicals: ResearchWorks – Volume 5 Number 10

I’ve written before about Energy Efficient Mortgages. The folks I spoke with at HUD felt the product was not particularly successful for reasons such as lender acceptance, difficulty of estimating savings, and general disinterest.

Now comes HUD ResearchWorks to highlight a renewed push via the Housing and Economic Recovery Act of 2008. In addition to the usual ‘tasking of HUD’ laundry list, HERA 2008 increases the approved cost of the energy efficiency upgrades to 5% of the property value from the previous cap of $8000.

I am hoping to catch up with some more HUD folks either at NBM or at December’s EcoBuild and provide additional information.

Field guide to weatherstripping

Not long ago I could not have identified more than two types of weatherstripping if you placed me on aisle 16 of Home Depot and gave me an hour to study.

Fortunately, before my trip today, I was able to brush up with the DOE’s helpful guide to weatherstripping. This afternoon I replaced my door sweeps, installed some tubular rubber door stripping, and inspected the silicone around my windows. Even without an infra-red visualizer I’ve noticed a difference.

I also bought two programmable thermostats for installation next weekend. More tales from the home improvement world to come.

Greener Buildings: Water saving tips

I’m still reviewing some of the data on a major efficiency drive at one of my properties, but the initial read is that we may have reduced water use by 30%+ after a six week program. Once I’ve confirmed the initial results I’ll share them in greater detail.

In the meantime, I’m happy to highlight an article from a company I really admire, Melaver of Savannah.

I encourage everyone to read the entire article, but two overlooked items really jumped out.

The first is placing irrigation on a separate meter where your water utility will allow it. The reason for doing so is to remove water used for non-potable purposes from the sewer bill. In a place like Knoxville, where we’ve encountered astonishing increases in sewage rates, this kind of separation can provide a payback in under 2 years.

The second idea is looking at aerators. Changing the aerators from the usual 2 gpf to ones that reduce flow to 0.5 gpf makes a real difference. We use conical aerators, which allows sediment to settle at the bottom but not impede water flow.

Water Savings 101: Top 10 Tips for Commercial Buildings | GreenerBuildings: “”

(Via Greener Buildings.)

Energy costs of open plenum and dropped ceilings compared

BD + C ran a nice summary of a study comparing the construction and heating costs of open plenum with dropped ceiling systems in retail and commercial settings. The Ceilings and Interior Systems Construction Association (CISCA) conducted the study.
[Note: For those who don’t traffic in HVAC jargon open plenum means you can see the vent work (think warehouses) while dropped ceiling means the ceiling is hung off of the bottom of the upper floor and all the mechanical systems are hidden (think law office)]

Although construction costs were cheaper for the open plenum design regardless of building type, the energy savings generated by the dropped ceiling system generated a payback period of 5 years in commercial buildings and as little as 11 months for food stores.

I’m a little surprised at the stark energy savings, but when you consider that you’re heating and cooling perhaps 20% more volume in an open plenum system it starts to make more sense. In a Memphis clubhouse project, we’re going with open plenums, but that’s largely because we’ve installed some passive cooling designs that would be obstructed by a dropped ceiling system.

Open Plenum v. Dropped Ceiling — CISCA Study