The US government has set up a special agency within the Department of Energy called the Advanced Research Projects Agency (ARPA) to promote “Disruptive and Innovative Approaches” to clean technology.  ARPA has the following objectives (from the ARPA website):

1. To bring a freshness, excitement, and sense of mission to energy research that will attract many of the U.S.’s best and brightest minds—those of experienced scientists and engineers, and, especially, those of students and young researchers, including persons in the entrepreneurial world;
2. To focus on creative “out-of-the-box” transformational energy research that industry by itself cannot or will not support due to its high risk but where success would provide dramatic benefits for the nation;
3. To utilize an ARPA-like organization that is flat, nimble, and sparse, capable of sustaining for long periods of time those projects whose promise remains real, while phasing out programs that do not prove to be as promising as anticipated; and
4. To create a new tool to bridge the gap between basic energy research and development/industrial innovation.

ARPA is currently supporting R&D in the following areas:

• Better batteries
• Technologies the reduce carbon emissions in coal powered power stations
• Grid scale energy storage
• Material advances in magnetic, high voltage switching and charge storage.
• Electrofuels – microorganisms to harness energy and convert carbon dioxide into liquid fuels
• Energy efficient building cooling technologies

This is an exciting program, and I particularly like the focus on breakthrough technologies. For example one of the energy efficiency cooling technology projects ARPA is supporting is thermoelastic cooling. This is a space cooling system that could have a a COP (coefficient of performance) up to 175% better than current vapour compression refrigerant systems.

It would be great to have a program similar to ARPA here in Australia.

I’ve decided to write this blog in a somewhat different format than usual. I thought I should share some of my observations in tracking energy use since I’ve been involved for a little while now in installing, analysing, presenting and monitoring ‘real time tracking systems’ (or ‘carbonrealtime’) as we refer to it.

I was actually really shocked to learn recently -when an environment officer at one of the councils posed the question to a small business audience, whether they knew how much power they used, how much their tariff rates were or how much their actual bills were- that most didn’t have a clue. Out of about 35 people only one knew. The rest had no idea! Even more surprising was the fact that a few of these audience members were accountants and financial advisors. They just automatically pay their bills both at home and for their businesses. How are you supposed to reduce your electricity use, cost and of course greenhouse emissions if you don’t even know (or care) how much you use and pay?

So there are a number of ways to overcome this problem of knowing your electricity use. Starting with the analysis of basic yearly use of the bi or three monthly bills you can get a bit of an idea what’s happening throughout the year. However, many of the larger sites already have interval electricity meters. These record power consumption every 15 minutes and eventually send some aggregated data to the suppliers. This information can be requested free of charge from the electricity retailer and we usually do this on our client’s behalf. Having access to at least a year’s worth of data is extremely useful. If you know how to compile the data and what to look out for one can get a really good idea of a site’s usage profile and how to save energy.

If your site doesn’t have interval metering another option is to install temporary electricity loggers on various distribution boards. Again the data obtained from this is very useful and we often do this for specific circuits at some of the sites. However, the latest revolution is in online tracking. We have developed an affordable real time tracking system that is extremely easy to install and then it’s plug and play. Once set up the device sends the data through the internet and can be accessed from anywhere. The user-friendly interface on the monitor presents all the data in an easy to understand language with graphs and images that don’t need a physics degree to understand. Some of our systems have everything incorporated such as water, gas, electricity consumption/generation and temperature. All these are highly valuable tools for any facilities or environment managers and even for educational purposes.

The ‘carbonrealtime’ systems are used in households and offices greatly reducing energy consumption but schools and council buildings have also installed them to keep an eye on their energy use. From some of these systems a few sites have already identified huge wastage that occur out of operating hours during the night or weekends. The findings from larger council site had effected changes in the HVAC BMS in relation to public holidays, starting and finishing times or discovering faulty equipment or in one instance double charging of electricity over 12 years! Lowering the base load is another useful outcome of using such a system. The tracking system can also be employed to overcome electricity apportioning disputes between tenants, which we often have to investigate for our clients.

With electricity prices going up constantly and with the emphasis on reducing greenhouse emissions; monitoring your electricity consumption is no doubt one of the most important steps towards averting huge electricity bills and the threats of climate change.

Commissioning is a quality-assurance process designed to increase the likelihood that a newly constructed building will meet client expectations. Commissioning stretches over the entire design and construction process. It should ideally begin at the design phase, with selection of a commissioning provider who helps ensure that the building owners and designers’ intent is written into the project documentation.

The design and construction of ‘green’ buildings pose problems similar to those found in conventional building design. This compromises the intent of the design to achieve a high level of energy efficiency in its function. A good sustainable design will include systems that are “right-sized” (rather than the typically oversized mechanical systems) for the building. Over sizing equipment has become a standard design practice, because—due to design, installation, and/or operation errors, systems rarely function at their intended capacity. These errors occur because of the fragmentation between design, construction and operation, resulting from a general lack of a systems approach in the building process. Commissioning can facilitate improved integration and communication between these phases and can also ensure that right-sized systems function as intended and as specified.

If a building is not properly commissioned, it will not perform according to its design intent and will therefore have a poor energy rating. A common reason for inadequate commissioning is the tendency for projects to go over time and budget and for the contractors to drastically pull back on resources to get started on new projects. For this reason, it is widely recognised that engagement in independent commissioning is best practice, as it is carried out objectively without any conflict of interest.

The cutting of costs and resources at the initial commissioning stage will end up costing the facility more money in the long run, as extensive maintenance issues will ensue. Also, the cost of retrofitting is always more financially intensive than implementation as part of the original build.

In conclusion, it is recommended to allow sufficient investment capital to employ independent commissioning at the construction stage, as it will save countless amounts of energy, money and time overall.

At the recent All Energy expo in Melbourne (early October) I came across the Coolerado cooler, distributed in Australia by Clear Solar. This is an ingenious, simple air cooler based on a combination of evaporative cooling and plate heat exchangers to deliver cooler air than is possible with conventional evaporative cooling but without the use of a refrigerant. It therefore has the energy efficiency of evaporative cooling, but with the performance of refrigerative cooling in dryer climates.

For a detailed explanation of how it works visit the Coolerado website. Below is a quick technical summary using the psychometric chart. You may prefer the Coolerado website if you don’t understand the properties of air at different moisture levels as displayed in the psychometric chart.

The unit splits air into two streams, either side of a plate heat exchanger. Moisture is added to one stream – the working stream. Its temperature drops using the evaporative process. This then sensibly cools the air on the other dry side of the plate, the process stream. Some of the process air is then split off and made into more working air. Moisture is added to this too. This then cools further, and through the plate heat exchanger it then further sensibly cools the process stream. By doing this multiple times the resultant process air exits at near the dew point temperature of the air. And around half of the total air going through the system ends up as useful process air. 

The chart above shows the principal of operation marked on it assuming the process stream is split up 3 times and perfect evaporative cooling (ie to the wet bulb temperature). In the Coolarado 13 stages are used to get air down to near dry bulb temperature.

As you can see in the my chart below – for 35 degree air at 20% humidity (at sea level) with a conventional evaporative cooler we can get the temperature down to near the wet bulb temperature of 19 degrees, but at 100% relative humidity. With the Coolerado we can get the temperature close to the dew point of 9 degrees, or if we are only cooling to 19 degrees do so with a relative humidity of around 55%, which is perfectly comfortable.

A variable speed fan in the unit controls the air flow and thus the exit temperature and relative humidity of the air it supplies.

For hot dry climates the Coolarado can completely substitute conventional refrigerative air conditioning. And in more humid climates it extends the usefulness of evaporative cooling.

The Coolarado website also has a chart based on historical weather data for hundreds of sites world wide, showing its applicability, including several Australian cities. Or, if you know your local weather and can use a psychometric chart, its possible to figure out its suitability. In Australia for example the Coolarado is well suited for use in Adelaide.

I’m not sure of the maintenance regime for the heat transfer plates and cooling pads – presumably similar to those of a conventional evaporative cooler, and obviously the system whilst saving energy does use water.

In addition to the energy savings another advantage of the Coolarado is it doesn’t have any refrigerants in it, so you don’t need to worry about the global warming potential of any leaked refrigerant. And the only moving part is its fan, which is a high efficiency direct drive unit, reducing mechanical maintenance requirements. 

Innovations such as this are going to help enable a low carbon economy, and as prices drop will start drive it.

A zero net energy office building is one which consumes no net energy. Its an office that uses very little energy, then has some form of renewable energy to generate all the power it requires.

With current off the shelf solar technology, presuming little or no shading, its possible to get around 100 kWh  of energy per year per square meter of solar panels at latitudes of around 40 degrees, more in sunny locations at lesser lattitude. For a single storey building, with a roof covered with solar panels, and little shading, keeping office energy consumption to 100 kWh/m2 is easy, and in fact I’ve audited quite a few small offices that are nothing special but only use in the order of 100 to 120 kWh/m2. But a grid connect solar system nowdays costs in the vicinity of  $700 to $1,000 per square meter, which is pretty  expensive, so there are very few zero net energy offices in existence.

Aggressive energy conservation and use of off the shelf technology (like skylights) can mean that office energy consumption is kept down to somewhere between 30 to 50 kWh/m2, meaning only half the roof needs to covered with solar panels, or allowing for some shading. For example our office uses only 30 kWh/m2/year, but is shaded in winter, we could make it energy neutral now just by covering around 2/3rds of the roof in solar panels.

So it is possible now, in 2009, to have a zero net energy office, but its not easily affordable, yet. And if your office is 3 storeys or higher, its becomes very hard to achieve no matter what your budget.

Technological advances however, are happening rapidly and I believe that by 2020 a zero net energy low-rise office may be affordable. And importantly this should be achievable by retrofitting an existing office building, with no need to especially construct a new building. Some of these technological changes are:

• The emergence of LED lighting. Assuming by 2020 we have LED lighting of around 200 lumens per watt. Allowing for some daylighting, and good use of task lighting, it may be possible to have annual lighting use less than 8 kWh/m2/year.
• Computer efficiency improvements. Assuming that with thin client architecture and high efficiency monitors by 2020 an office PC uses 15 watts, and that a 200 watt server can then serve 30 clients, computer energy use would be around 3 to 4 kWh/m2/year.
• There are many likely pathways for HVAC, which will depend on climate. A likely pathway for temperate climates is 100% fresh air HVAC systems, with air to air heat exchangers, but also using legacy internal ducting to allow high flow full economy cycles. Fans will be highly efficient, and heat pumps will have high efficiencies at a range of loading conditions, with the conditioning of air separated from ventilation to lower fan energy use. Couple this with light weight retrofit phase change materials (PCM) to provide thermal mass (eg plasterboard with encapsulated PCM), white roofs (where there are no solar panels), glazing treatments and new insulating membrane technologies to improve the thermal performance of the building. Seal the building well, and combine with good use of sensors and intelligent control all of which limits HVAC energy use to say 15 kWh/m2/year.
• Miscellaneous loads: high efficiency fridge at say 150 kWh/year; near zero standby loss hot water system; high efficiency multi function devices, totalling say 4 kWh/m2/year.

This will result in total office energy use of around 30 kWh/m2/year.

With aggressive energy conservation occupants should be able to to get down to say 15 to 20 kWh/m2/year.

Assume solar panel efficiency is more than double current efficiency and the installed price per watt of a grid connect system is one third of the current cost. This will provide 260 kWh/m2/year at a cost of say $500 per square meter.

A single story unshaded office where aggressive energy conservation is practiced will then need only 8% of its roof covered with solar panels, at a cost per square meter of building area of only $40.

A three storey half shaded office building would need most of its roof covered.

It should be possible to have a 7 storey building energy neutral if unshaded and the roof is covered with solar panels. Of course if additional solar panels can be added to walls it should be possible to get even taller energy neutral buildings.

By 2020 the net zero energy low-rise office building should be easily affordable, and in fact it may well be standard good financial practice to convert existing office buildings to energy neutral ones. So even building owners with no interest in acting to slow climate change will have energy neutral buildings. And most low rise office buildings then – whether they are 100, 50, or 1 year old –  could be energy neutral.

I say “should” and “may” because I still have some doubt as to whether a couple of the technologies that modify the thermal performance of a building –  particularly PCMs, and retrofit membrane’s that improve its insulation properties – will be affordable. But then again with focus a lot can change in 11 years, and as more of us demand better energy performance from our buildings I believe that this will spark the innovation needed to make zero net energy office buildings common place.

You can help make this a reality by acting now to make your building more efficient. Do what is affordable now. Then repeat regularly - technology is now advancing quickly. You’ll create the demand that will drive the innovation that will create the technology that will make energy neutral buildings common place.