## 3 Findings for Each of the Three Layers
### Market Layer  
From the existing literature, it can be concluded that several incentives for smart grid environments are present at the market level. Namely, aggregators can operate on the spot markets, i.e., by energy arbitrage, and on the balancing markets [8], however, some market barriers are present. For example, in many European countries, it is impossible for renewable electricity generation to operate on balancing markets, while this generation is very suitable to use for downward regulation [46]. Another current market inefficiency is the risk that current renewables generation \begin{table}
\begin{tabular}{p{113.8 pt} p{284.5 pt}} \hline \hline
**Stakeholder Group** & **Description** \\ \hline \multirow{4}{*}{
\begin{tabular}{} \end{tabular} } & A residential customer or utility business that produces electricity. Roof top PV installations and energy storage battery systems are examples of homeowner investments that allow people to do both consume and produce energy for use locally or to export during certain parts of the day or year. \\ \hline \multirow{4}{*}{Aggregator} & A person or company combining two or more customers into a single purchasing unit in order to negotiate the purchase of electricity from retail electric providers, or the sale of electricity to these entities. Aggregators also combine smaller participants (as providers or customers or curtailment) to enable distributed resources to play in the larger markets. \\ \hline \multirow{4}{*}{Balancing responsic party (BRP)} & A legal entity that manages a portfolio involving the demand and supply of electricity, and has a commitment to the system operator in a European Network of Transmission System Operators for Electricity (ENTSO-E) control zone to balance supply and demand in the managed portfolio on a Program Time Unit (PTU) basis according to energy programs. \\ \hline \multirow{2}{*}{Balancing service provider (BSP)} & In the EU Internal Electricity Market, this is a market participant providing balancing services to its connecting transmission system operator (TSO), or in case of the TSO-BSP model, to its contracting TSO. \\ \hline \multirow{2}{*}{Supplier} & A supplier provides energy to end customers, based on a contract. The energy can be from the supplier’s own power plants or traded in relevant markets. \\ \hline \multirow{2}{*}{Distribution system operator (DSO)} & The DSO is responsible for the safe and secure operation and management of the distribution system. DSOs are also responsible for the planning and development of the distribution system. \\ \hline \multirow{2}{*}{Transmission system operator (TSO)} & A legal entity responsible for operating, developing, and maintaining the transmission system for a specific zone and, where apposite, its interconnections with other systems, and for guaranteeing the long-term ability of the system to meet reasonable demands for the transmission of electricity. \\ \hline \multirow{2}{*}{Government/Regulator market participants, regulators must be politically and financially independent.} \\ \cline{2-2}  & The regulator must strengthen competition and ensure that this does not compromise security of supply and sustainability. To act even-handedly in the interests of all market participants, regulators must be politically and financially independent. \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Stakeholders in smart grids environments and descriptions of their roles (adapted from [8])incentive schemes (especially feed-in tariffs) decrease the value of newly installed renewables generation over time. Smart grids can address this by more efficiently matching supply and demand. From a market perspective, one could argue that, when the shares of renewables in the grid increase to high levels, their inherent fluctuations would cause more volatile spot market prices and higher imbalance prices, thus providing higher incentives, and possibly business models, for smart solutions.