Number of participants
Chapter 4: Analysis and Findings Barriers to Adoption
4.2 Thematic Analysis: Barrier Themes Identified
4.2.5 Environmental
4.2.5.2 The Maintenance Challenge
The frequency of cleaning the solar panels in the UAE due to the already explained impact of sand and dust was also observed as a key barrier from an environmental point of view. The apparent challenge was expounded by additional issues such as the unpredictable need for cleaning, its cost, the limitation of both manual and automated cleaning, and some other concerns. There were twenty-three participants who cited this barrier as a problem.
a) Technical Participants‘ Opinions
A group of four architects, three architects with research background, four PV specialists, and seven other consultants all seem to agree with the idea that maintenance of BIPV in the UAE is a challenge which needs adequate attention. The high frequency of cleaning stands as one of the first issue here (R05AE; R08ARE; R24PVU; R25PVE;
R26OCE; R28OCE). One participant added, ―the panels have to be cleaned regularly, and it needs quite a lot of water, and that is the one that puts people off.” This last comment was made by a mechanical engineer who had done some research with solar panels in the UAE and he added the maintenance is not only intensive, ―...but the main problem is the unscheduled maintenance; that kills you” (R28OCE). Other professionals agree that cleaning can be as high as twice a month (R24PVU; R32OCE; R05AE), and other PV technologies like concentrated PV may require weekly intervals. (R08ARE). It was also noted the cost due to maintenance is in part unpredictable and unknown due to the weather variations (R17ARE; R28OCE).
Furthermore, the practical challenges with various cleaning methods were clearly outlined. Firstly, clients with solar panels installed need to be in close communication with manufacturer to handle the cleaning regimen (R20PVE), unlike one non-technical participant assumed (R57CE), residents cannot install and “you just put it on there”. The actual issue however is that manual cleaning requires the use of buckets and mops in a labor intensive and inconvenient process (R05AE; R08ARE; R28OCE). Two participants detailed the difficulty as follows:
“…I have to open a hatch in my ceiling, pull down a ladder, climb up it, get water thru the hatch on to my roof, get on to it, which has a parapet which is only 400mm high. So, really, I shouldn‟t be going up there, or asking any family members or people who work for me to go up there.” – R05AE
“…nobody is ever happy to climb up on the roof and clean the panels every other day. So that is not going to happen.” – R28OCE
Another professional noted that manual cleaning using rope climbers is less safe and incurs a higher operational expenditure (OpEx). He was comparing this option with that of mechanical cleaning systems using a Building Maintenance Unit (BMU) which he suggested was safer but comes with a higher capital cost (CapEx). He also added that the BMU takes up roof space which the client wishes to use for other functions (R05AE). Describing the limitation of automatic or machine cleaning, the cost was raised as its first challenge (R26OCE; R35OCE). ―We checked the automatic cleaning, it was massive expensive, the cost was very massive and very, very expensive in regard to automatic cleaning” (R35OCE). The other issue raised, however, was that the high-tech panel wipers require a lot of water, recycled grey water used would smell and washed sand particles could block drains.
“Wipers on PV panels? Surely, you‟d have to inject some sort of fluid, as in water, which again is expensive here, to clean the panel. Now we could possibly use gray water, but then you‟d start to get a smell, and it‟s not ideal because then you‟ve got
the runoff of the water, where does it go? Does it go back down the drainage system
…Yeah; it means all sorts of trouble. And the drains get blocked with sand, so anything water-based here is an issue, unfortunately.” – R26OCE
These opinions seem to paint a compelling picture against the use of BIPV in the region as these participants infer that all methods would need some space for access to clean and, or a catwalk (R05AE: R28OCE;). It is also important to note that the UAE has a desert climate and water is a prime natural resource which barely exists naturally, compared to tropical contexts for example; and it comes from an expensive desalination process. In a nutshell, due to maintenance, BIPV is considered as a technology-intensive and expensive strategy (R05AE; R28OCE) which pales in comparison to the cheap energy - unsustainable but less expensive (R28OCE). But one participant distinguished between large and small projects, and arguing that ―…for big projects, the cost of maintenance is small compared to the cost savings” (R33OCE). Nonetheless, going beyond cost concerns related to this maintenance challenge, one professional admitted she did not know much about how to the clearing of the panels is carried out (R07AU).
One PV specialist, however, contradicted this narrative about the frequency of cleaning solar panels stating that the traditional curtain walls and BIPV curtain wall require the same cleaning frequency. He added that vertically positioned BIPV panels collect less dust than when inclined.
“At 24 degrees, you will need cleaning every 2 weeks…Cleaning cycle is the same with traditional curtain wall. It is a misconception that BIPV requires more than normal buildings…I should say that with vertical panels they collect less dust and require less intense cleaning than roof installations.” – R18PVE
This distinction between BIPV roof and curtain types presents a divergent view which is debatable. However, another fact argued was the need for highly skilled and
experienced rope climbers for manual cleaning (R05AE). One participant noted with some uncertainty,
“…I do not think that there are enough companies in the UAE to do this. No local companies to handle this” (R33OCE).
b) Non-Technical Participants‘ Opinions
Views of two Client-Expats, two PMIs and one participant from the developer group respectively suggest a correlation in opinion with the technical narrative. The anxiety that frequent cleaning (R64PMI; R68D) was raised along with the need for access to clean (R68D). Also raised was the concern that cleaning would be difficult and require a specialist with expert knowledge, occupant risk and safety measures (R52CE).
A participant from the PMI group who was an architect had attempted a mechanical BIPV cleaning mechanism. He noted that it was fixed only for Estidama reasons which he believed was the main problem (R64PMI). He admitted that it did not work well but he was optimistic that the technology will improve.