Issue | Sep 2011

Solar-powered Air-conditioning System for Vehicles

Great news for drivers! They can now continue to keep the

air-conditioning system on during the hot sunny days even when they stop the vehicle and switch off the engine. In collaboration with Green Power Industrial Ltd, PolyU's Department of Electrical Engineering has developed an innovative air-conditioning system for vehicles that can turn scorching summer heat into cool air without a single drop of gasoline.

Motorists are so used to turn on the engine for air-conditioning. Our solar-powered air-conditioning system for vehicles (SAV) will break this convention. Featuring photovoltaic technology and intelligent power control, SAV switches on-board air-conditioner to solar power when petrol engine shuts off, and the switch-over is automatic and seamless.

Principal investigator of this project Prof Eric Cheng explained, "Drivers of minibuses or taxis can now switch off

the engine but continue to stay cool while waiting for passengers at the station. In fact, our system helps extend the operation of air-conditioner for two more hours." Prof Cheng further stressed that this device can also give good power output even during cloudy or rainy days.

Similar to a big solar charger, this system has solar photovoltaic panels on the rooftop of the vehicle to collect power for storage in a battery to support a stand-alone electric air-conditioning unit when the car engine is not running. The solar panel is made from bendy materials which can fit perfectly on any vehicle rooftop, giving it a sleek appearance. It also serves as a good thermal insulation for the interior and other valuable equipments inside the vehicle.

Idling not only pollutes the air, but is also bad for the engine as it may contaminate engine oil and

PolyU's green technology to keep the drivers cool

R

PolyU wins industry's support to promote solar energy on the road

The whole world is working towards sustainability and PolyU also plays an increasingly significant

role in its innovative and sustainable technologies. Our Department of Electrical Engineering

together with the partner, Green Power Industrial Ltd, have jointly developed an innovative

solar-powered system for vehicles that turns sunlight into electricity for an on-board

air-conditioner. In the near future, motorists will be able to keep the air-conditioner on when the

engine is not running. Not only does it allow drivers of taxis, minibuses and trucks to enjoy in the

cool during summer while the engine is off, but it can also help save energy, restrict harmful

emissions as well as reduce the effects of climate change. What a cool idea!

Issue | Sep 2011

Tel: (852) 3400-2929 Fax: (852) 2333-2410 Email: pdadmin@inet.polyu.edu.hk Website: www.pdo.polyu.edu.hk

accelerate the deterioration of engine components due to higher operational temperature and unnecessary prolonged operation. According to recent statistics, leaving a vehicle on idle for as short as 10 minutes a day will consume an average of 100 litres of petrol in one year [1]. In other words, adopting our SAV can help save drivers' petrol and fuel cost.

PolyU's President Prof Timothy W. Tong hailed the device as a practical solution that could benefit thousands of professional drivers and pedestrians in the city. The installation of our SAV on a Swire Coca-Cola Hong Kong truck was first announced in October last year. A series of testing on the road have proven the system robust and effective. To make another milestone on the road to green transport, the system is now being widely deployed in public transport such as minibuses and taxis, as well as some commercial vehicles including an operation truck of the Airport Authority Hong Kong.

"We look forward to having more fruitful collaboration with Green

Power Industrial Ltd and other industrial partners to build a low-carbon city. Together, we can jointly make a contribution for sustainable development of our community," said Prof Tong.

As part of an on-going mission in advancing technology that safeguards natural resources and our ecosystem, SAV is the latest from a stream of PolyU's green innovations with an aim to reduce harmful emissions and eliminate the effects of climate change. This system has also brought home two international awards from the 39th International Exhibition of Inventions of Geneva in April this year. This accolade will certainly serve as recognition of the hard work, the know-how and the dedication that PolyU researchers have put in creating meaningful innovations that move us towards a sustainable society.

[1] George Pakenham, “How a single

New York citizen is improving roadside air”

The system has been installed on different types of vehicles

Solar private car

The System Components

Awards from 39th International Exhibition of Inventions of Geneva

Issue | Sep 2011

司機們在炎熱天氣停了車、關掉引擎，

但仍然可以在車廂內享受冷氣，這絕對

是司機們的一大喜訊！理大電機工程學

系與陽光動力有限公司合作研發的嶄新

科技，正正可以把火猛的太陽能量轉化

成冷氣，不費一滴汽油，也不排一絲廢

氣！

一向習慣登車就開啟冷氣的司機們，如

今有了這套SAV太陽能汽車冷氣系統之

後，這種習慣或許要改變了。系統的光

伏發電技術配以智能電力控制，在引擎

關閉後即啟動太陽能驅動的冷氣系統，

便可繼續為車廂提供冷氣。

研發SAV技術的首席研究員鄭家偉教授解

釋：「有了這套系統的幫助，營業車如

小巴、貨車或計程車的司機們，就可以

在等候期間關掉汽車引擎而同時繼續享

用冷氣，其實，系統仍能在關掉引擎

後提供兩小時多的冷氣。」鄭教授也

強調，這套系統應用了優化的設計，同

樣可在陰天或雨天中應用。

這系統類似大型的太陽能充電器，它在

車頂上放置多塊太陽能光伏板來收集太

陽能，並存於電池之內，當汽車引擎關

掉後，就有足夠電力支援一台獨立的

空調裝置。太陽能光伏板以軟性物料

製造，方便配置於任何的車頂上，光滑

而美觀，同時，光伏板也能為車廂或車

內貴重的儀器帶來了絕緣的效用。

停車而不關引擎不但浪費汽油，更為社

會帶來空氣污染。根據最近公布的數據

顯示(註一)，就算每天只讓車輛空轉十分

鐘，每年都會多花了平均一百公升的汽

油。換言之，使用了SAV系統就能讓車主

節省了汽油的支出。

理大校長唐偉章教授相信這系統能為

職業司機提供一個既涼快、又環保的

方案。該系統獲得太古可口可樂香港有

限公司的大力支持，讓系統置於一輛汽

水車頂作實際應用測試，並在去年十月

系統研發成功的發布會上展示。其後，

汽水車再作連串的路面測試，確認了系

理大與業界合力推廣太陽能汽車冷氣系統

太陽能汽車冷氣系統成功面世理大綠色科技滿足司機「熱」切期待

全球的科技都朝可持續發展的方向前進，而理大在創新科技及可持續發展的技術方面，正扮演著一個愈益

重要的角色。最近，我們的電機工程學系與企業合作夥伴陽光動力有限公司，攜手為交通工具成功研發了

一套創新的太陽能汽車冷氣系統，可把太陽能轉化成為電力，供應汽車冷氣之用。當司機應用了該系統之

後，縱使關掉了汽車引擎，卻仍然可以安坐車廂，享受冷氣帶來的舒適。在炎熱的天氣下，不單計程車、

小型巴士及貨車等交通工具的司機可以受惠，系統還有助車輛節省能源，能為社會減少廢氣排放，同時減

少氣候轉變帶來的影響，難怪會令人們「熱」切期待！

統有效及優秀的性能。而為了把綠色運

輸的發展推向另一里程，SAV再廣泛地

安裝於其他公共交通工具上，如小型巴

士、計程車，以及商用車輛如香港機場

管理局的工程車等。

「我們期望與陽光動力有限公司合作發

展更多有益社會的項目，一起為建設低

碳城市而努力，繼而為我們社會的可持

續性發展貢獻綠色力量。」唐教授說。

理大目前正進行的科研項目，包括多項

致力減少有害排放及應付氣候變化的綠

色科技，SAV就是其中一項先進的環保技

術。這系統並於第39屆瑞士日內瓦國際

發明展中榮獲兩項國際殊榮，對我們

理大的科研人員來說，他們多年來不

斷以專業的知識、不懈的努力以及莫

大的付出為社會持續的發展創新有意

義的發明，這些榮譽遠道帶來，無疑是

重要的肯定和推動力！

註一：節錄自George Pakenham著作《How a

single New York citizen is improving

roadside air》，網址：http: //www.cleartheair.

org.hk/idling-engines.php

Issue | Sep 2011

Tel: (852) 3400-2929 Fax: (852) 2333-2410 Email: pdadmin@inet.polyu.edu.hk Website: www.pdo.polyu.edu.hk

太陽能汽車冷氣系統已經安裝在多種交通工具上

太陽能私家車

系統元件

於第39屆瑞士日內瓦國際發明展中榮獲兩項國際殊榮