In large-scale systems for domestic hot water supply with and without heating support, the Proportionate Energy Savings, according to DIN CEN/TS 12977-2, are presented in the project report. Proportionate Energy Savings = ($Q_{\text{conv}}$ - $Q_{\text{aux}}$) / $Q_{\text{conv}}$ $Q_{\text{conv}}$ represents the energy consumption of a conventional reference system. (Term in the standard: “Gross energy requirement of the reference system”) $Q_{\text{aux}}$ is the conventional energy consumption of the simulated solar system, i.e., the energy supplied to the system by auxiliary heating. »

The economic calculation in T*SOL® using the net present value method is based on the following formulas: Investment Costs = Installation Costs - Subsidy Yearly Operating Costs = Pump Performance * Operating Time * Electricity Costs The Net Present Value (NPV) of a price-dynamic payment sequence Z, Zr, Zr², … over T years (lifespan) according to VDI 2067 is: $ NPV = Z * b(T, q, r) $ $b(T,q,r) = \begin{cases} \frac{1 - \left(\frac{r}{q}\right)^T}{q - r} & \text{if } r \neq q, \\ \frac{T}{q} & \text{if } r = q \end{cases}$ »

Enhanced Calculation of Swimming Pools In T*SOL®, swimming pool systems (indoor and outdoor) are now simulated. In practice, conventional swimming pool heating systems are increasingly complemented by solar installations. T*SOL® assists planners in calculating the energy savings of such combinations. The existing swimming pool simulation model in T*SOL® has been fundamentally revised and improved: Differentiation between private and public pools Consideration of (hourly) presettable usage times by bathers Consideration of potential shading portions of the water surface New algorithms for calculating radiation gains, distinguishing between diffuse and direct radiation components More accurate capture of cloud influence New algorithms for calculating evaporation and convection New thermodynamic model for covers The improved algorithms have been validated using measurement data [^1] (see Fig. »