diff --git a/src/main/java/info/peper/vz/rest/VzRestController.java b/src/main/java/info/peper/vz/rest/VzRestController.java
index f6b9bc2..4f0a445 100644
--- a/src/main/java/info/peper/vz/rest/VzRestController.java
+++ b/src/main/java/info/peper/vz/rest/VzRestController.java
@@ -34,14 +34,24 @@ class VzRestController {
 	}
 	
 	@GetMapping("/rest-vz/sums")
-	Sums getData2(@RequestParam("timestampStart")final long timestampStart,
+	Sums getData(@RequestParam("timestampStart")final long timestampStart,
 			@RequestParam("timestampEnd")final long timestampEnd,
-			@RequestParam("houseId")final int houseId) {
-		final List<Aggregate> aggregates = jdbcTemplate.query(
-				"SELECT MIN(timestamp_start) AS min_ts_start, MAX(timestamp_end) AS max_ts_end, SUM(produced_energy)/3600 AS sum_produced, SUM(obtained_energy)/3600 AS sum_obtained, SUM(injected_energy)/3600 AS sum_injected FROM volkszaehler.tobias_aggregate2 WHERE house_id=? AND timestamp_start>=? AND timestamp_end<=?;", 
-				(rs, rowNum) -> new Aggregate(houseId, rs.getLong("min_ts_start"), rs.getLong("max_ts_end"),
-						rs.getLong("sum_produced"), rs.getLong("sum_obtained"), rs.getLong("sum_injected")),
-				houseId ,timestampStart, timestampEnd);
+			@RequestParam("houseId")final int houseId,
+			@RequestParam("solarFactor")final float solarFactor) {
+		final List<Aggregate> aggregates;
+		if (solarFactor == 1.0f) {
+			aggregates = jdbcTemplate.query(
+					"SELECT MIN(timestamp_start) AS min_ts_start, MAX(timestamp_end) AS max_ts_end, SUM(produced_energy)/3600 AS sum_produced, SUM(obtained_energy)/3600 AS sum_obtained, SUM(injected_energy)/3600 AS sum_injected FROM volkszaehler.tobias_aggregate2 WHERE house_id=? AND timestamp_start>=? AND timestamp_end<=?;", 
+					(rs, rowNum) -> new Aggregate(houseId, rs.getLong("min_ts_start"), rs.getLong("max_ts_end"),
+							rs.getLong("sum_produced"), rs.getLong("sum_obtained"), rs.getLong("sum_injected")),
+					houseId ,timestampStart, timestampEnd);
+		} else {
+			aggregates = jdbcTemplate.query(
+					"SELECT MIN(timestamp_start) AS min_ts_start, MAX(timestamp_end) AS max_ts_end, SUM(produced_energy * ?)/3600 AS sum_produced, SUM(GREATEST(obtained_energy + produced_energy - injected_energy - ? * produced_energy, 0))/3600 AS sum_obtained, SUM(ABS(LEAST(obtained_energy + produced_energy - injected_energy - ? * produced_energy, 0)))/3600 AS sum_injected FROM volkszaehler.tobias_aggregate2 WHERE house_id=? AND timestamp_start>=? AND timestamp_end<=?;", 
+					(rs, rowNum) -> new Aggregate(houseId, rs.getLong("min_ts_start"), rs.getLong("max_ts_end"),
+							rs.getLong("sum_produced"), rs.getLong("sum_obtained"), rs.getLong("sum_injected")),
+					solarFactor, solarFactor, solarFactor, houseId ,timestampStart, timestampEnd);
+		}
 		if (aggregates.size() != 1) {
 			throw new RuntimeException("Interal error in SQL query.");
 		}
@@ -75,7 +85,8 @@ class VzRestController {
 	String getSummary2(@RequestParam(name = "timestampStart", defaultValue = "-1")long timestampStart,
 			@RequestParam(name = "timestampEnd", defaultValue = "-1")long timestampEnd,
 			@RequestParam(name = "duration", defaultValue = "")final String duration,
-			@RequestParam("houseId")final int houseId) {
+			@RequestParam("houseId")final int houseId,
+			@RequestParam(name = "solarFactor", defaultValue = "1.0")final float solarFactor) {
 		
 		if (!"".equals(duration)) {
 			final Duration dur = Duration.parse(duration);
@@ -102,7 +113,7 @@ class VzRestController {
 		for (EnergyPrice price : prices) {
 			final long tsStart = Math.max(price.getTimestampStart(), timestampStart);
 			final long tsEnd = Math.min(price.getTimestampEnd(), timestampEnd);
-			final Sums sums = getData2(tsStart, tsEnd, houseId);
+			final Sums sums = getData(tsStart, tsEnd, houseId, solarFactor);
 			savedMoney += (float)(sums.getProduced() - sums.getInjected())/1000000 * price.getPrice();
 			totalProduced += sums.getProduced();
 			totalObtained += sums.getObtained();