H2OOL APPLICATION
How to Use It
The H2ool, downloadable has been created to be user friendly, producing information required efficiently and effectively. The results typically take around 5 minutes to generate and collate using the H2ool and the user is only required to input the demand and irradiance data.
As stated previously the tool is highly flexible can be made adaptable to any size of demand and will effectively deliver outputs that can satisfy the respective irradiance data that has also been input by the user.
As the tool currently stands, the user may wish to input their whole demand whether it be for a community, household etc. whereby it is assumed all the solar energy harnessed goes to the electrolyser OR they may wish to input the demand at times whereby there is no or insufficient irradiance so they are only storing hydrogen to satisfy these times.
Applying the Tool
To investigate the feasibility of the solar-hydrogen system for deployment, the group utilised the H2ool whereby the applied it to two contrasting climates, going on to compare each. The feasibility for deployment is mainly considered in terms of PV size area (m2) required for each respective storage size and the resultant capital cost for each as these are the key variables.
For this, a demand profile was simulated which was equivalent to that of the University of Strathclyde’s Campus (on average 50 UK houses).
Figure 1: Low Irradiance Climate
Case 1: Low Irradiance climate
First, the H2ool was implemented for the case of a low irradiance climate, such as Glasgow. It is clear from the graph below that the system is not particularly viable for such a climate whereby the optimum choice was that of the largest storage size. This option still required a PV array area of around 1.5 football pitches, which is unfeasible particularly in the case of city centre implementation.
Case 2: High Irradiance climate
Secondly, the H2ool was implemented for the case of a high irradiance climate; the data was taken from Arizona – one of the most solar rich areas in the world. As to be anticipated this is a much more feasible option whereby the optimum can be seen as the ‘2x’ storage size however the PV array area is still equivalent to approximately 1 football pitch.
Figure 2: High Irradiance Climate
Climate Comparison
The H2ool guarantees effectiveness – moreover in a stochastic context however we can see that the results are not particularly cost effective comparing them to other methods of energy production as detailed in the economic analysis section.
Regarding both reliability and economic viability of the system, mainly regarding PV area and cost, the following options were considered best for each climate.
Table 1: Climate Comparison
As to be expected, the high irradiance climate presents a stronger case for the system deployment... On further investigation it was calculated that if the low irradiance climate was to have the same PV array area as that of the high irradiance climate, it would require ‘15x’ the storage size.
The results appeared to be somewhat counterintuitive as both cases have similar costs incurred for generation (£/kWh) however this is due to the dominating costs of the electrolyser and fuel cell which remain constant in the case of the same demand. Potential for reducing these costs are discussed in ‘Future Work’.