Grab a strand of hair from your head, and examine it. Now imagine if that strand were 10,000 times thinner, and what you’ll be holding will be the equivalent size of future light emitting diode (LED) lights. At the thickness of only three atoms, Scientists Xiaodong Xu and Jason Ross at the University of Washington have developed the thinnest possible LED lights.
LEDs have been around for many years, though only recently has their usage become widespread in exterior vehicle lighting, traffic lights, signs, seasonal and interior lighting. LEDs create light by electroluminescence, which is the phenomenon of material emitting light when electricity passes through it. Electroluminescence was discovered in 1907 independently by scientists H. J. Round and Oleg Losev. In addition to light-emitting applications, this technology could open doors for using light as “interconnects,” to run nano-scale computer chips instead of standard devices that operate off the movement of electrons, or electricity. The latter process creates a lot of heat and wastes power, whereas sending light through a chip to achieve the same purpose would be highly efficient.
As the size and price of LEDs decreases, new applications are arriving to the marketplace in the construction industry. Lights can be more easily integrated directly into building materials such as paneling, moldings, ceiling tiles and even flexible carpets. Some very interesting uses are being experimented with using portable rugs and carpets for children with neurological disorders such as autism. When affected children are experiencing extreme mood changes such as tantrums, multicolored LEDs can be activated within a carpet remotely to produce calming effects. Cutting edge research is attempting to correlate the impact of light color and pulsation on brainwave activity. Different patterns of light can also be used to evoke stimulating brain activity as well. One can only imagine what possibilities lay ahead in the medical arena.
In another more novel application, two global leaders in lighting and carpeting recently announced a partnership to develop “light transmissive carpets,” capable of turning floors into displays. The key was to replace the traditional rubber carpet backing with something that could transmit light and stand up to the heavy wear and tear of foot traffic. The result was a thin steel screen containing an array of ultrathin LEDs.
One of the first applications for the new floor covering will be for animated signage on the floors of airports, theaters, hotels and other public areas, not only to guide people to their destination but also to facilitate efficient evacuation in the case of an emergency. From a purely aesthetic standpoint, the lighted carpet could not only enhance ambience but declutter busy areas making information visible only when it’s needed. From there, it’s only a matter of time before we’ll see it incorporated into interactive gaming technologies.
These new applications stretch the imagination and get us excited about the future but here at Thayer Corp we are integrating new LED features into buildings today. Unlike incandescent or fluorescent lights, LEDs have linear dimming characteristics, meaning that light levels and power consumption is directly proportional to the setting 0-100%. Combined with Smart control features, we can program light levels to follow daylight patterns, time-of-day usage patterns, occupancy and security needs. A wireless controller such as a smart phone, tablet or PC can be used to adjust programming. In an occasionally used room, such as a conference room, light can be set at 5-10% levels yet immediately jump to 100% upon occupancy via integrated motion detection and return to the user selected unoccupied levels during normal working hours and completely off during unoccupied, non-working hours. The motion of forklifts in warehouses can immediately activate lighting without warm-up delays and return them to preprogrammed ambient light level minimums for life safety requirements once the activity passes.
We often forget the impact of after-hours housekeeping on energy consumption. It’s quite normal for housekeeping to flip on all the lights for six to eight hours at night while a very small crew moves within large buildings cleaning. Smart controls could be programmed to allow the light to “follow” their movement, greatly reducing energy use without compromising their effectiveness or safety.
Parking lot lights can be dimmed to some preset level such as 30-40% after evening hours, yet immediately all come up to 100% the moment any motion is detected anywhere in the lot. Would-be vandals and burglars might be a bit startled!
Dimmability, smart controllability, and steadily declining prices are making LED lighting a more cost-effective choice while we wait for the more innovative and cutting-edge applications to become commercialized. Ask our experts for an audit today and how you might qualify for incentives from Efficiency Maine.
This winter season has set many records for severity across the entire US and Canada. One record it’s unlikely you’ll find data on is freeze-ups and frozen pipes within buildings. Anecdotally, there are a record number of these unfortunate disasters this heating season. Frozen pipes often burst, causing severe building damage and loss of use, and are extraordinarily difficult to thaw. Not only have we experienced severely cold weather, but the coincident wind has made the “chill factor” of buildings much colder than usual.
Often there are conflicting views on protecting hydronic heating systems with antifreeze. Practitioners such as plumbers and heating technicians are often poorly informed, relying upon wholesalers for information. Even system designers are frequently misinformed. The debate is often emotional and illogical, so here are a few facts to help you make a good decision about its use.
The type of antifreeze used in HVAC systems is typically glycol. Most of the glycol used for these applications has added corrosion inhibitors. Some benefits of adding inhibited glycol to a system include:
Prevention of system freeze-ups and bursting pipes and coils when properly applied.
Allows for deeper temperature setbacks without a freeze risk resulting in reduced energy usage.
Reduced corrosion within piping, boilers, coils and valves leading to longer life.
Reduced scaling in boilers and heat exchangers thus maintaining higher efficiencies.
Minimal issues with toxicity (if propylene glycol is used).
All of these benefits presume that the glycol solution is properly maintained annually.
Some of the risks or disadvantages are:
Initial cost of adding and maintaining solution.
Slightly higher pumping power required.
Reduced heat transfer from coils, heat exchangers and boilers.
Larger expansion volume necessary.
More difficult air elimination from system.
System flushing and clean-up might be required on “dirty” systems before the addition of glycol.
Let’s explore these a bit more. First, it’s necessary to determine which protection level you need. Some prefer to protect to a very low temperature point by adding more glycol, say to as low as 0-10°F. It’s also possible to protect the system to “burst point,” which is approximately 30° lower than the freeze point, say -30 to -20°F. At the freezing point, the solution won’t flow, but the pipes and coils won’t rupture. Once heat and/or pumping are restored, the “slushy-like” solution melts and becomes fully liquid again. The higher the concentration of glycol, the higher the first cost and negative impact on heat transfer and pumping power. Generally, it makes sense to protect to the higher burst temperature criteria. For example, a 20% solution of propylene glycol by volume would yield a freezing point of 17°F, a burst temperature of approximately -10°F, require 3% more pump power for equivalent flow, and impede heat transfer by 3%. This alone cannot be the total answer as to system performance.
The glycol used for heat transfer applications is generally propylene glycol (P/G) with corrosion inhibitors. Ethylene glycol also has good performance characteristics, but due to toxicity concerns, we don’t recommend its use. P/G is very different from automotive antifreeze, which contains silicates which tends to gel, impeding flow and causing problems especially in flow control valves. P/G is not toxic and is widely used in many applications such as a solvent and carrier of flavor or color in the food and beverage manufacturing processes, to make drinks, biscuits, cakes, sweets, as a thickener, clarifier and stabilizer in consumables such as beer, salad dressings and baking mixtures. P/G is also used to keep tobacco semi- moist. Ever wonder what keeps Twinkies soft for so long?
The maximum working temperature of the P/G solution is 250°F. For ordinary heating applications, this isn’t at all a problem, but care must be taken on closed-loop solar heating systems. It is quite possible for the fluid flow to become stagnant in the collector plates if the controls aren’t properly working. Temperatures can easily reach this upper limit causing the P/G to break down and become acidic.
Occasionally, P/G is added to hydronic systems that provide cooling (i.e. ice arenas). Obviously the working temperature for cooling is much lower than heating which results in a much higher solution viscosity. This more viscous solution is harder to pump and impedes heat transfer more than at higher temperatures. Both of these disadvantages must be planned for.
The corrosion inhibiting properties of glycol reduces scale build up, especially in boilers. Scaling is quite common and reduces heat transfer significantly; for example, a 1/8” scale build up in a boiler results in 30% more fuel usage overshadowing the minor heat transfer loss from the addition of antifreeze. As the performance and efficiency of boilers and heat exchangers has steadily increased over the past two decades, the surfaces have become greater and passages smaller making them much more difficult, if not impossible, to clean this scale buildup.
Many of the strong opinions about glycol in HVAC systems from designers, installers and service technicians are a reaction to some of the challenges working with the solution. A few of the major challenges are:
A water/glycol (aqueous/glycol) solution has a lower surface tension than water alone and will leak where water doesn’t. This is especially true on automatic air bleeding valves, causing “weeping.”
Glycol is an “oxygen scavenger,” making air elimination much more difficult during the initial system fill. It can take several days to bleed all of the air out of a system.
Annual maintenance is required to assure that the concentration, pH and general fluid quality are acceptable. Deficiencies generally can be corrected by adding more glycol, corrosion inhibitors and/or pH correction. Neglected systems can turn acidic and deteriorate pipes, valves, fittings and equipment.
Care must be taken not to isolate sections of piping or equipment such as a valve; the solution needs to be able to expand into the expansion tank upon a system freeze event such as power outage.
The expansion tank needs to be slightly larger than a water only system.
Automatic fill valves should be eliminated to prevent inadvertent concentration dilution in case of a small leak. These lists aren’t intended to be a complete list of do’s and don’ts or design considerations, but hopefully provide more information to help guide your decision. If interested, consult one of the professionals at Thayer to determine the feasibility for you system. There’s nothing worse than the expense, damage and the “coulda, shoulda, woulda” that often follows a catastrophe such as a building freeze up. Act now, and “Call in the Experts.”
After months of negotiation, Congress passed a comprehensive farm bill Tuesday on a vote of 68-32. It was a rare display of bipartisanship and a hopeful sign proving that Congress can find common ground on key legislative activities. The bill approved allocates a whopping $1 trillion dollars although there were significant cuts to many agricultural subsidies. Of keen interest to us here at Thayer is the funding for alternative fuels. While some argue that the free market should be used to determine what fuels are best, it’s one of the few tools available providing parity for biomass heating fuels and technologies outside of comprehensive tax reform. The oil and natural gas industries receive huge subsidies in the form of tax incentives and direct subsidies from both the Federal government and States.
The bill’s energy title provides mandatory funding for programs including:
Rural Energy for America Program (REAP): Provides resources to business owners to help finance the installation of renewable energy systems or upgrade existing systems, including those utilizing biomass. Mandatory funding of $50 million per year has been designated and the application process has been simplified and streamlined.
Bioenergy Program for Advanced Biofuels: Provides direct payments to advanced biofuel producers, including those manufacturing pellets. Mandatory funding of $15 million per year has been designated.
Biomass Crop Assistance Program (BCAP): Provides financial assistance to owners and operators of agricultural and non-industrial private forest land who wish to establish, produce, and deliver biomass feedstock. This program was allotted $25 million in mandatory funds annually, and the collection, harvest, storage and transportation (CHST) payments will resume, with limitations.
Community Wood Energy Program (CWEP): The program was altered to allow for grants of up to $50,000 establishing or expanding biomass consumer cooperatives to facilitate purchase of biomass heating systems or products (including their delivery and storage). This program was authorized at $5 million annually, though no mandatory funds were allotted.
The BCAP program could help jumpstart diversification of biofuels used for heating such as fuel crops that could be planted and harvested with little environmental impact. Maine is well suited to grow a majority of the fuel needed for its growing pellet business allowing for alternatives to the harvest of wood. Northern Maine is especially well suited for fuel crops.
The president has expressed his support of the bill and his signature is expected later this week. This bill will boost utilization of biomass heating systems in Maine and across the US.
This winter season has been one of the worst in recent history. Gelid temperatures and widespread power outages have been recorded in many parts of the country due to crushing winter storms and bitter, dangerous wind chill factors. But that isn’t the entire story; unprecedented demands have been placed on electrical and gas distribution systems and infrastructure. Although lately we’ve experienced a nice January thaw, the next wave of the pain will be sharply escalating energy costs. Maine has experienced shortages of natural gas. That, paired with the recent ice storm, has created high premiums for the power produced and distributed by electric utility companies. As regulated utility companies, they are allowed to pass all of these costs to consumers (read more here).
Nationally and especially in the Northeast, both gas and electric infrastructures are in dire straits. Vastly overdue improvements, replacements and capital spending have been deferred for decades. Although the gas industry boasts that newly-tapped gas fields will serve energy needs for decades, gas distribution from well heads to end-users will be problematic and expensive, which means increased future energy cost.
Hoards of manufacturers and vendors boast that you should buy their silver bullet. It’s hard to choose the best vendor, since they all promise you the most savings. The best way to stretch your dollar is with a proactive and comprehensive preventative maintenance program. On average we save clients 10 to 20% of energy costs on allegedly “adequately” maintained systems. The common business model in the HVAC Service industry is to price the preventive maintenance agreements as “loss leaders;” perform absolutely minimal maintenance and make money from repairs. We offer many types of preventive maintenance agreements and will tailor one for you to achieve your desired savings. All have verifiable tasks and some offer full guarantees. Put the “monkey” on our back, and don’t be left outside during this cold winter. Call in the experts for an audit on your system.
Lately, much of the United States has experienced unseasonably cold weather for the month of December. Record lows have been recorded in many states. While no meteorological records have been set in Maine this month, the weather has been colder and snowier here also. This early winter has us seriously concerned about energy cost and supplies in Maine.
Electricity in Maine is purchased from other states and produced locally from a variety of sources including renewables and hydro. Increasingly, power is produced from gas-fired power plants. When gas was plentiful and relatively cheap we enjoyed the benefits of stable electricity costs. As gas distribution pipelines lately have been extended to many new communities and businesses, conversion to gas has been very popular. Unfortunately, this has pushed the limit of existing gas pipeline capacity in our region.
Last Saturday afternoon (December 14th), a new record of sorts was set. The spot market price for electricity in Maine set a record at $1.00 per Kw/Hr. The “spot market price” is the price of power that one utility company pays another for power. The typical price is $0.02 to $0.06 per Kw/Hr, thus this peak price was nearly a staggering 1700% spike! Most electric utilities buy power on the spot market for their daily peak power demands. These daily peaks are biggest during the Monday through Friday work week, reflecting the combined demand of business and residences. The typical daily peak demand duration is two to six hours, and happens twice a day, morning and late afternoon/evening. Saturday’s record spot price wasn’t due to the unusual demand, as it was on a weekend, or the uncharacteristic wintry weather. This record price is a frightening precursor of energy price hikes to come. These extremely high spot market prices ultimately will be borne by ratepayers.
So then, why was the cost so high? Ironically, efficient natural gas-powered generators were operating at extremely reduced capacities due to a shortage of gas at the Calpine power plant in Westbrook, while a few miles away the Cousins Island oil-fired power plant (that is frequently idled) ran at full capacity. It burned expensive oil and spewed comparatively high emissions to the atmosphere. Last year, the Cousins Island plant produced power for only one day out of the entire year. Even more ironic is the fact that the Cousins Island plant is for sale; a buyer has been located and has likely scheduled demolition for next summer to clear the site for a residential assisted living community development.
The long-term solution will require additional gas pipeline capacity and/or imported Canadian purchased power. Both of these solutions will be contentious, political, costly, and at minimum require three years for completion. In the meanwhile energy conservation remains our best value.
