energy - Andre Rozendaal

Energy prices are rising quickly, so having clear insight into your consumption is essential. Below is my energy usage and system configuration.

📊 This Year at a Glance

Hover over (or tap) an underlined term for its definition.

Self-Sufficiency (2026)

46.9%

PV Self-Consumption (2026)

50.1%

Solar Produced YTD

6 092 kWh

Battery Efficiency (2026)

76.0%

🏘️ Compared to Similar Homes

	Mine (2025)	Average	Difference	Rank
Gas (m³)	223	1 360	-84%	better than 90%+
Net electricity (kWh)	827	2 620	-68%	better than 78%
Energy bought (kWh)	3 006	15 907	-81%
Water (m³)	105	163	-36%

Total energy used in 2025: 9 416 kWh = 7 237 kWh electricity + 2 179 kWh gas. Of the electricity, 3 292 kWh (45%) came directly from my own solar panels (incl. via the battery). CBS only measures what passes the meter, so the table compares energy bought.

Compared with: Corner houses of 100–150 m², built before 1946, with 4 residents (CBS StatLine 85140NED, 2025). Water: typical 4-person household (Nibud/Vitens).

📈 Yearly Overview

Bars: electricity used at home (own solar + grid import) next to exported solar. Line: gas (m³, right axis).

📅 Yearly Totals

Year	Grid import (kWh)	Grid export (kWh)	Solar (kWh)	Gas (m³)	Water (m³)	Battery in (kWh)	Battery out (kWh)	Battery eff. (%)	PV self-cons. (%)	Self-sufficiency (%)
2026	3 454	3 037	6 092	125	92	818	622	76.0	50.1	46.9
2025	3 945	3 118	6 410	223	105	829	626	75.5	51.4	45.5
2024	5 165	3 422	5 525	185	94	–	–	–	38.1	28.9
2023	3 923	2 511	3 878	572	23	–	–	–	35.3	25.8
2022	3 131	3 132	4 438	763	0	–	–	–	29.4	29.4
2021	4 214	63	127	1 148	0	–	–	–	50.4	1.5
2020	2 776	0	0	493	0	–	–	–	–	0.0

🗓️ Monthly Breakdown

2026

Month	Grid import (kWh)	Grid export (kWh)	Solar (kWh)	Gas (m³)	Water (m³)	Battery in (kWh)	Battery out (kWh)	Battery eff. (%)
Nov	106	18	65	4.7	1.8	14	11	75.7
Oct	408	139	377	6.6	9.0	70	53	75.9
Sep	255	222	520	5.6	8.6	88	67	76.5
Aug	247	382	779	6.1	9.2	98	75	76.6
Jul	96	583	897	3.1	6.4	96	72	75.0
Jun	207	412	844	8.4	10.5	99	76	76.6
May	177	454	862	8.0	10.4	109	84	76.7
Apr	194	518	858	9.1	9.2	94	71	75.9
Mar	330	247	553	11.2	9.6	88	68	76.7
Feb	603	46	223	13.0	8.7	37	27	74.0
Jan	832	18	115	49.0	8.8	25	18	73.9

2025

Month	Grid import (kWh)	Grid export (kWh)	Solar (kWh)	Gas (m³)	Water (m³)	Battery in (kWh)	Battery out (kWh)	Battery eff. (%)
Dec	602	7	107	43.0	8.6	–	–	–
Nov	485	32	176	23.0	8.2	–	–	–
Oct	406	68	258	6.0	8.4	–	–	–
Sep	226	287	560	5.0	8.5	–	–	–
Aug	120	497	779	5.0	7.4	–	–	–
Jul	89	162	831	2.0	9.7	–	–	–
Jun	146	465	871	9.0	9.9	–	–	–
May	95	583	919	7.0	9.1	–	–	–
Apr	116	528	825	9.0	9.0	–	–	–
Mar	236	357	690	12.0	8.6	–	–	–
Feb	609	98	269	48.0	8.3	–	–	–
Jan	815	34	125	54.0	9.4	–	–	–

2024

Month	Grid import (kWh)	Grid export (kWh)	Solar (kWh)	Gas (m³)	Water (m³)	Battery in (kWh)	Battery out (kWh)	Battery eff. (%)
Dec	737	10	52	44.0	8.4	–	–	–
Nov	620	66	168	11.0	8.6	–	–	–
Oct	417	169	339	7.0	8.4	–	–	–
Sep	349	364	563	5.0	7.4	–	–	–
Aug	227	583	812	5.0	7.4	–	–	–
Jul	197	610	812	4.0	6.4	–	–	–
Jun	208	510	806	3.0	8.0	–	–	–
May	220	526	779	4.0	7.5	–	–	–
Apr	310	359	617	9.0	8.5	–	–	–
Mar	458	165	346	8.0	8.2	–	–	–
Feb	630	24	106	22.0	7.7	–	–	–
Jan	792	36	125	63.0	7.7	–	–	–

2023

Month	Grid import (kWh)	Grid export (kWh)	Solar (kWh)	Gas (m³)	Water (m³)	Battery in (kWh)	Battery out (kWh)	Battery eff. (%)
Dec	692	10	48	40.0	7.7	–	–	–
Nov	562	29	98	30.0	7.3	–	–	–
Oct	419	88	197	4.0	7.7	–	–	–
Sep	275	230	402	5.0	0.0	–	–	–
Aug	190	275	461	3.0	0.0	–	–	–
Jul	203	354	501	6.0	0.0	–	–	–
Jun	196	455	646	8.0	0.0	–	–	–
May	183	408	547	12.0	0.0	–	–	–
Apr	215	320	434	52.0	0.0	–	–	–
Mar	274	174	268	104.0	0.0	–	–	–
Feb	283	123	185	131.0	0.0	–	–	–
Jan	431	45	91	177.0	0.0	–	–	–

2022

Month	Grid import (kWh)	Grid export (kWh)	Solar (kWh)	Gas (m³)	Battery in (kWh)	Battery out (kWh)	Battery eff. (%)
Dec	393	44	80	182.0	–	–	–
Nov	364	73	154	59.0	–	–	–
Oct	287	163	263	7.0	–	–	–
Sep	222	277	395	4.0	–	–	–
Aug	201	416	567	4.0	–	–	–
Jul	189	438	593	4.0	–	–	–
Jun	186	426	582	4.0	–	–	–
May	189	414	571	12.0	–	–	–
Apr	210	354	469	61.0	–	–	–
Mar	227	374	508	73.0	–	–	–
Feb	292	119	188	148.0	–	–	–
Jan	371	34	68	205.0	–	–	–

2021

Month	Grid import (kWh)	Grid export (kWh)	Solar (kWh)	Gas (m³)	Battery in (kWh)	Battery out (kWh)	Battery eff. (%)
Dec	354	33	64	216.0	–	–	–
Nov	349	30	63	154.0	–	–	–
Oct	380	0	0	55.0	–	–	–
Sep	350	0	0	8.0	–	–	–
Aug	335	0	0	7.0	–	–	–
Jul	270	0	0	5.0	–	–	–
Jun	382	0	0	4.0	–	–	–
May	373	0	0	50.0	–	–	–
Apr	225	0	0	60.0	–	–	–
Mar	388	0	0	152.0	–	–	–
Feb	373	0	0	186.0	–	–	–
Jan	435	0	0	251.0	–	–	–

2020

Month	Grid import (kWh)	Gas (m³)	Battery in (kWh)	Battery out (kWh)	Battery eff. (%)
Dec	418	216.0	–	–	–
Nov	345	134.0	–	–	–
Oct	386	82.0	–	–	–
Sep	328	9.0	–	–	–
Aug	378	7.0	–	–	–
Jul	286	7.0	–	–	–
Jun	306	11.0	–	–	–
May	329	27.0	–	–	–

🏠 Home and Energy System

I live in a corner house built in 1908, heated by a gas boiler and three air conditioners.

📋 House Facts

Type / year built: Corner house, 1908
Floor area / volume: 103 m² / approx. 444 m³
Heat-loss surface: 155 m² exterior wall (incl. windows), 70 m² roof
Energy label: D (2020 – 2030)
Issued before all upgrades below
Heating: Vaillant ecoTEC plus + Tado, plus 3 air conditioners on 2 outdoor units, north + south (heating since 2023)
PV: approx. 6.3 kWp (south + east/west)
Storage: HomeWizard 2.7 kWh / 800 W

🔄 Net Metering and Future

Net metering ends in 2027. After that, depending on energy prices, a battery becomes even more useful.

🔧 Upgrades and Installations

2021 – Sunpower solar panels
10 × Sunpower P3-380-BLK panels facing south, connected to an SMA Sunny Boy 3.0 inverter.
2023 – Major renovation
Insulated the roof, added or renewed interior insulation on all exterior walls, and insulated all ceilings so heat stays in the rooms being heated. Replaced the kitchen window and frame, and removed the kitchen's outside door.
2023 – Air conditioners
Installed 3 air conditioners on 2 outdoor units: a multi-split on the north side for the living room/kitchen and the office, and a single split on the south side for a bedroom.
2024 – Eurener solar panels
6 × Eurener 410 Wp panels facing east/west, with an AP Systems inverter.
2025 – Home battery
2.7 kWh HomeWizard battery with an 800-watt inverter.
2025 – HR++ glass
Replaced old double-glazed windows with HR++ glass.

🔭 Planned Improvements

Larger home battery (~7 kWh)
Replace the HomeWizard; its 800 W charging is too low on sunny days.
Heat pump
Sizing based on heat-loss measurements via the air conditioners in Home Assistant.

Data from Home Assistant · Last updated: November 07, 2026