Evaluation of the energy performance of UC Davis’ Net-Zero Community


In the global competition for appealing clean energy solutions, a leading entry is the new West Village at the University of California at Davis (UC Davis), which today celebrated significant progress toward its goal of becoming the largest planned “zero-net energy” community in the United States.

Seven years ago, I was one of nine jurors who selected the winner in a competition to establish the nation’s first university-based center on energy efficiency (and yes, it’s hard to believe that this didn’t happen until 2006!). UC Davis finished first in a distinguished field, and it has more than justified expectations in the years since.

Among the Energy Efficiency Center’s proudest achievements is the beautifully designed space next to the main campus that bills itself as the nation’s largest planned community to reach “net zero” – annually consuming less electricity than it produces while emitting no carbon pollution.

The “West Village” is proceeding in stages and will ultimately house 3,000 students, along with 500 staff and faculty families and a cluster of retail and commercial buildings. By making those buildings far more energy efficient than even California’s rigorous standards require, the West Village architects were able to balance all their projected electricity needs with onsite solar photovoltaic (PV) power production. The UC Davis Center made a commitment to regular evaluations of the West Village’s performance, too, and the inaugural report was released today.

In the first year of substantial occupancy and fully powered PV systems, roughly 1,500 people in more than 500 apartments and a half-dozen mixed-use buildings came hearteningly close to “zero net-energy”: about 87% of the way, to be precise. Thanks to local experts from the Davis Energy Group, we know pretty much exactly what caused the gap, and what to do about it.

The solar power systems performed pretty much exactly as advertised, although the evaluators think we can squeeze out a few more megawatt-hours of electricity with occasional cleanings of the solar panels (to remove dust emanating from local agricultural operations). Also operating as predicted were the buildings’ cooling and heating systems, and the one- and two-bedroom apartment units taken as a group. Consumption was higher than expected in two principal categories: three- and four-bedroom units, whose occupants loaded up on plug-in electronics and showed remarkable variation in monthly electricity use; and water heat, where a high-efficiency technology relatively new to U.S. markets (heat pumps) created some siting and operational problems that contributed to higher power use.

The West Village managers are confident that they can cover the remaining distance to “zero net energy” and I agree with them. The water heating glitches are already mostly fixed. For the larger apartments, a host of strategies are being deployed to identify and motivate the largest electricity users to waste less energy, starting with the repeatedly proven social science insight that the best way to change behavior is simply to show people that their neighbors are doing better.

Regular performance reports will help with that message, as well as show the world continuing progress and any remaining barriers to reaching the community’s laudatory goals.

The next West Village performance review is due in early 2015. I look forward to sharing the results, and I’ll close with the quote that I authorized for use in the news release accompanying today’s report:

“The West Village is what a sustainable energy future looks like for California and the rest of the world. Its commitment to comprehensive evaluations like this one is an important part of the good example that the community is setting for all the rest of us.”

Article by Ralph Cavanagh, a senior attorney and co-director of the energy program at the Natural Resources Defense Council.
Link to article: http://switchboard.nrdc.org/blogs/rcavanagh/what_the_future_looks_like_wes.html

Deadly flash flood event in Mauritius on 30th March 2013 – How SUDS can help reduce flooding risks

Deadly flash flooding event in Mauritius on 30th March 2013

Deadly flash flooding event in Mauritius on 30th March 2013

It is very saddening and shocking to see that 11 people have been victims (so far) of the tragic flash flood event on the 30th March 2013 in Mauritius. My thoughts are with the families who lost their dear ones and those who have lost their property and belongings during this event.

I am not an expert in drainage system design or flood risk management, however I would like to share some information that I have gathered during my career, regarding reduction of flooding risk through the implementation of SUDS (Sustainable Urban Drainage Systems). I am providing the information below, in the hope that the engineers/designers who will review the drainage system in Mauritius after this terrible event, might take SUDS into consideration. 

Flash floods are terrifying events, that can be very destructive and deadly, as we have witnessed. Localised heavy rains, together with inadequate drainage and increasing urbanisation can lead to severe problems due to flash flooding after sudden heavy rainfall. Cutting down vegetation to replace them by artificial surfaces such as impermeable concrete and tar means the area loses its ability to absorb rainwater. The rain is therefore directed into surface water drains instead, causing them to be overloaded and resulting in floods. Whatever we do on land will affect the hydrology of an area.

All it takes for flooding to become a problem is for 40% of vegetated area to be cleared and replaced by impervious surfaces such as impermeable concrete. The amount of surface water runoff will then double and flow twice as fast. Extreme rainfall events can cause hundreds of mm of rainwater to fall within a few hours – this amount of water flowing at high speed on impervious concrete areas will certainly overload drainage systems, which cannot dispose of the water as quickly as they are receiving it.

There are several ways of managing stormwater. The more traditional way is to divert water runoff from drains into rivers (“rapid conveyance” approach). However, the water runoff is sometimes so rapid that the rivers just cannot cope with the sudden deluge, leading to flooding downstream. When drains and rivers are blocked by debris, the water flow is impeded, worsening the flooding event.

Retention ponds hold water run-off back and slowly release it to mitigate flooding

Retention ponds hold water run-off back and slowly release it to mitigate flooding

Another way of managing rainwater runoff is to use the “control at source” concept. This means increasing the time that the water takes to reach streams by controlling it at source. This is a totally different approach from the rapid conveyance method. Water runoff is first captured and then gradually released or allowed to infiltrate the soil. Therefore, instead of a sudden, excessive water flow to areas downstream, the water flow is mitigated and reduced, making it more likely for drains and streams to be able to cope with it.

A swale

A swale

However this requires that the water runoff from the site must be similar to or less than levels before land-clearing took place. This means that developers should be responsible for limiting the rainwater discharges due to their construction when a vegetated site is changed into an artificial impervious one. Instead of merely building drains to cater channeling of rainwater away from their development site, they should contain the water instead and release it gradually or allow it to seep into the soil. We should not work against nature, but with it. We should try to mimick nature’s natural hydrological cycle through a combination of infiltration, storage and delayed stormwater flow. The approach to replicate natural drainage systems is termed the SUDS (sustainable urban drainage systems) approach, sometimes termed “sustainable drainage systems” as they are not restricted to urban areas only. SuDS have a low environmental impact by managing water runoff through collection, storage, and natural cleaning before it is allowed to be released slowly back into water courses (drains and rivers). Usually SuDS constitute a combination of water retention ponds, wetlands, underground storage tanks, infiltration, permeable surfaces, swales, and filter drains with the best combination of structures and techniques being specific to the site in question.

Permeable paving especially useful in car parking spaces to allow for subsurface infiltration

Permeable paving especially useful in car parking spaces to allow for subsurface infiltration (image courtesy of RIBA Sustsainability Hub)

The way we manage rainwater runoff should be reviewed and alternative ways of managing stormwater could be explored and evaluated, as well as the establishment of by-laws to guide the implementation of more sustainable and natural stormwater management practices, replicating natural attenuation, infiltration and drainage, rather than relying solely on concrete-lined drains. The benefits of both water storage and infiltration strategies extend beyond that of controlling water runoff. They also improve water quality, encourage bio-diversity, add amenity value and help us adapt to and mitigate the negative impacts of climate change.

Emma Ozsen
Sustainability Consultant

Energy Star and EU Energy labels


You must have noticed either of these symbols on electric appliances in the past few years.  ENERGY STAR and the European Union Energy label  are trusted symbols for energy efficiency and help guide consumers to protect the climate through energy-efficient products and practices.

When you buy domestic appliances or even energy-efficient light bulbs, check for the ENERGY STAR label or the  EU Energy label. The labels mean these products are certified to use less energy.

So , next time you shop for appliances, electronics, home / office equipment, lighting, etc. look out for these labels to save energy and money!

Mauritius: UNESCO conference on climate change education opens

world-300x209Balaclava, Mauritius – A three-day experts’ meeting on climate change, sponsored by UNESCO, kicked off Wednesday in the northern Mauritius city of Balaclava.

The Mauritian Education Minister, Vasant Bunwaree, who spoke at the opening session, said that education for sustainable development would pave the way for a better comprehension of issues related to durability of the planet.

“Our  understanding of education today is constantly punctuated by an awareness of the new realities and global preoccupations,’ he said.

He added ‘there is now a wide recognition that something is changing in our climatic system.’

He said that extreme climate events, such as heavy rains and tropical storms, have been increasing over the last few years, let alone the rise in temperatures, the sea level and the deterioration of the coastline as well as ‘the reduction of the water resources which are all risks we are constantly confronted with’.

Recommendations from the meeting will be turned over to the 18th United Nations conference of the Framework Convention on climate change and the UNESCO world conference on sustainable development education scheduled in 2014 in Japan.

Source: http://www.afriquejet.com/news/4075-mauritius-unesco-conference-on-climate-change-education-opens.html

Global Warming: how can you help and save money at the same time?

global_warmingWe can ALL make a difference. Every action we take, however small it may seem, makes a difference. Whether you decide to recycle, to reduce the time you spend in the shower, or plant your own vegetables, we all have the power to make changes in our life and help reduce the harm we cause to nature. Here are some simple ways you can help reduce your negative impacts on the environment and, at the same time, on your pocket.

If you are still using incandescent lamps, you are not only paying more than you should but also causing a lot of energy wastage and carbon dioxide emissions.


Replace your light bulbs with either CFLs (compact fluorescent lamps) or LEDs (Light Emitting Diodes). For more info about CFLs and LEDs, have a look at this Facebook post I made a little while back about CFLs and LEDs: https://www.facebook.com/media/set/?set=a.519714178069968.1073741826.116618288379561&type=1&l=d292cbd318

Use paper products with recycled content whenever possible (for example, use  100% post-consumer recycled printer paper, recycled paper towels and napkins).

Air-cons use up a lot of energy to cool down the air and releases the heat into the environment. Many air conditioners also contain hydrofluorocarbons which contribute to the depletion of the ozone layer. They also have a negative impact on our bodies’ natural adaptation to hot and cold temperatures. If you are used to blazing cold air conditioning, try to raise the temperature a little bit more everyday and you will see it’s not so bad! Maybe you can even go without or use a fan instead?

If you use an electric shower, it is likely to account for a major part of your water heating costs. Taking shorter showers will not only reduce your electricity bill but also reduce the negative impact you have on the environment. Even better, invest into a solar water heater and you will only use natural heat energy from the sun to heat up your water.

unplugDid you know that by keeping your electronics plugged in, you are wasting huge amounts of energy. Save energy by making sure your phone charger, TV, blow dryer, etc. are unplugged when they are not being used!

When you wash your clothes, choose the cold wash setting on your washing machine for clothes that are not very dirty. You will save energy by not heating up the water. Air-drying your clothes rather than using a tumble dryer. We are lucky to have sunshine all year round, so why not make use of it!

Fuel prices are climbing at an astounding rate, so why not save some money and at the same time do something good for the environment by carpooling to work/school. Try to organise carpooling yourself and suggest it to friends. If your place of work is at walkable distance, walk or ride your bike instead.

Recycle as much as you can (paper, plastic, glass…) and buy products which have less packaging when you shop. You will save a lot of carbon dioxide from being released into the atmosphere by doing those simple acts to reduce your garbage.

Ecology-and-Economics-The-Sustainable-Future_widgetDo you enjoy gardening? Plant a tree in your yard or take a plant along to your workplace. Not only will it make you feel better, but you will also reduce the amount of CO2 in the atmosphere. A single tree will absorb a ton  of CO2 over its lifetime!

Different kinds of plastic take different times to degrade. Most plastic bottles will sit in landfills for several hundreds of years! Even worse, bottles made with Polyethylene Terephthalate (PET or PETE) will never biodegrade. Very few plastic bottles are recycled, meaning a lot of them also end up thrown in public places or in the sea. toxicPlastic thrown into the warm sea water gets broken down more quickly with UV rays (this can be in as little as a year) and toxic chemicals such as bisphenol A (BPA) and PS oligomer are released. These either end up in the digestive systems of of sea animals or get washed up onto the shore, where we humans are most likely to come into direct contact with the toxins. Who loves a swim in toxic water?  Mauritius is blessed with lovely beaches that we are meant to enjoy safely. So, please share and either don’t go for plastic bottles, recycle them if you do use them and don’t throw them in watercourses or the sea! Use glass bottles as far as possible. Most of them can be returned to the shop where y0u buy them, and you even get some money back for doing so!

Does any of the tips above speak strongly to you? What else do you think can be done by us individuals to help reduce global warming? Let me and other fans know on my Facebook page

Emma Özsen
Sustainability Consultant & Building Design Analyst

Emma Ozsen

Green-Fingered Mauritian Farmers Go Green

“We no longer can afford to buy chemical fertilisers. The subsidised compost will bring down the cost of our inputs, besides giving a new life to our dying soil.” says Kripalou Sunghoon, a farmer from Triolet.


In fact, it has been about 2 months now since the Mauritian government teamed up with a private compost-manufacturer to offer farmers here a 30% subsidy for compost made from domestic waste and an increasing number are realising the benefits of going green.

Read the full article here:

Sustainable building design analysis using Ecotect

If you are an architect, building designer or engineer, you might have heard of Ecotect Analysis. If you haven’t, it might be of interest to you. Students or professionals in the construction industry willing to go towards sustainable design might also find this useful in understanding the design principles through a visually responsive and interactive tool.
[NOTE: I am also planning on providing training courses on the fundamentals of Ecotect, as well as green building design concepts, in the near future (see last paragraph of this article).]


Ecotect is a tool designed to aid in the simulation, analysis and optimisation of high performance buildings, and is especially useful in sustainable building design projects. Its comprehensive analysis capabilities help analyse and simulate conceptual designs. It allows architects and engineers to test and evaluate design strategies and to study alternatives and make decisions earlier to deliver more achievable, resource-efficient building designs.

Architects, designers and engineers often find it useful to visually communicate complex design concepts and extensive datasets to other project team members and clients in an intuitive and effective way. For instance, proposing the use of a shading device might not be initially accepted by a client, until the potential savings in cooling energy due to the shading device is demonstrated. This can effectively be done through the use of Ecotect Analysis.

Using simulation software, design professionals are able to continuously study and predict how decisions will impact the performance of the building from the early phases of design through occupancy, reducing or eliminating the need for investment in mock-ups or manual calculations. Ecotect gives architects, designers and engineers the power to use performance-based criteria in their design projects.

Ecotect Analysis produces cutting-edge 3D spatial models to help users visualise  the simulation output, allowing a smooth translation of the simulation results into the project design.  A few of the outputs from Ecotect Analysis are shown below (all images courtesy of Autodesk):


If you are interested in learning how to use Ecotect for conceptual design analyses, I am planning on providing training courses on the fundamentals of Ecotect as well as an overview of green building design concepts. Courses will be MQA-approved and fees refundable up to 75% (for companies contributing to the HRDC levy grant system) . If you are interested in attending the training course and would like to be notified when the training courses are scheduled, please subscribe to this blog or to the Facebook fan page.
If you think your friends might be interested in the above, please share this using the social media buttons below.  

Emma Ozsen - Sustainability Consultant
Emma Ozsen
Building Design Analyst and Sustainability Consultant

Green building and sustainability

If you are in the construction and design industry, you probably very often hear the words “green building” and “sustainability” nowadays. The use of these two key terms can create confusion through misstatement and misconception. Green building and sustainability do not mean the same thing, and yet we often see them being used interchangeably. This is understandable – both concepts contain similar underlying elements and are often interconnected. In order to explain the key differences between the concepts of green building and sustainability, it is very important to understand the actual meaning of both.

Green building, or building green, is essentially building based on concrete and responsible actions to reduce harmful impacts on the immediate environment. For instance, in a green building process, the building materials chosen are those with little or no amount volatile organic compounds (VOCs) and have low embodied energy. The efficient use of water via water-saving appliances, water/greywater recycling and rain water recycling are also considered in the development of green buildings. All these are all tangible actions which reduce the negative environmental impacts of the building procedure.

As for sustainability, it is not just an environmental concept, but it is in fact but made up of three spheres, encompassing environmental, economical and social components. Therefore, in a way, sustainability is much more complex than merely saving energy or reducing carbon emissions. In terms of ecology, the word sustainable describes how biological systems remain diverse and productive over time without causing irreversible damage to the ecosystem’s health. In the human context, it is the potential for long-term maintenance of wellbeing, which in turn depends on the wellbeing of the natural world and the responsible use of natural resources. In terms of the construction and design industry, it is the process whereby consumption (either of a material or of energy) is undertaken only when it is organically maintainable.

One common misconception that I come across is the use of “green technology” to define green building. Does the addition of solar panels on a building make the latter green? Solar power provides “free” energy, not requiring the burning of fossil fuel, therefore using solar power reduces harmful impacts on the immediate environment. However the resources it takes to manufacture solar panels and the disposal of the often toxic remains of the solar panels and batteries is not sustainable! Take the example of solar air-conditioning. Using solar power is a green act but if the building was not designed to limit and naturally dissipate solar heat gains through careful passive design, then the use of the panels does not make up for the fact the the building was poorly designed in the first place. I mentioned this fact in one of my very first presentations at the Eco-building conference in 2010, as I wanted to highlight its importance. If a building is not designed with the right passive strategies in mind, then sticking Photovoltaic panels on top of it does not make it a truly green, let alone sustainable, building!

It is the holistic environmental process that is sustainable, not merely the technology or material. For example, building with wood is, in itself, a green building practice because wood is a durable, natural resource however, if the wood is not FSC (Forest Stewardship Council)-certified, then it is simply not sustainable. Building with wood sustainably means that the environment is not being damaged faster than it can be renewed through replanting. In order to be truly sustainable, the wood should be sourced locally from a wooded area that is replanted so as not to leave lasting environmental damage.

In conclusion, it is easy to confuse these two key terms, “green” and “sustainable” – not everything labelled as “green” is really good for the environment or sustainable. You need to use your judgement to make careful choices in order not to be greenwashed!

Emma Ozsen - Sustainability Consultant
By Emma Ozsen
Building Design Analyst and Sustainability Consultant