Ambient energy systems (AES) are expected to be the basis for making a noticeable improve­ment in the quality of life experienced indoors. The key barriers to the greater use of AES by designers fall under three headings: lack of experience, lack of information and cost pressures. Taking each of these in turn, the chief contributions […]

Detailed Design

From the detailed design (section 7.5) it can be seen that the alternative energy source for both cases taken here could include a battery, such as Figure 7.21. The solar sensor might also be used with an external transformer, as in Figure 7.22. User information for the solar calculator is relatively intuitive as the user […]


Conclusions can be drawn for the two case studies from all four of the subsections in section 7.4. From subsection 7.4.1 it can be seen that PV module appearance may be more easily resolved for the solar calculator than the solar sensor. This is because the solar calculator colour is likely to be closer to […]

Storage selection

Last in this conceptual phase is the selection of charge storage. For the case of the solar calculator, the storage required is low (see subsection 7.6.1) and self-discharge should not be a limiting factor. For the solar sensor, the requirements are the opposite. Significant storage capacity is required (e. g. a month without radiant energy), […]

PV technology

The radiant energy available is a determinant of the appropriate photovoltaic technology, as concluded in section 5.6 and described in subsection 7.3.2 (PV technology section). The electrical efficiency can also be improved in a number of ways; the principles are outlined in section 4.7, while practical solutions are described in section 5.5. Such improvements can […]

Radiant energy

For the case of the solar calculator, the product must function with the radiant energy available at a desk. The solar sensor has more scope for influencing available energy: firstly, the position of the solar module in the built space, such as close to a window, as can be concluded from subsections 3.3.2 and 3.4.3; […]

Conceptual Design

The probability of product technical feasibility can be increased in a number of ways, which may be necessary either to relax initial constraints (see above) or to extend the envelope of feasible situations. The ways of increasing technical feasibility investigated in this work include optimising radiant energy collection and correctly selecting photovoltaic modules and charge […]


The first step in clarification is to determine the ball-park technical feasibility of the proposed product as shown in section 7.2. This feasibility depends on the amount of charge storage that the product will require. For very low charge storage capacity requirement products, such as solar calculators (e. g. less than 10 ^W h/day or […]