Why Is My Electricity Bill So High When I Have Solar Panels?

Last updated: August 2025

Have you recently received an electricity bill that is still significantly high despite having solar panels installed? If so, you are not alone. This is a frustrating situation for many Australian homeowners, especially those living along the Sunshine Coast. With the amount of sunlight the region receives, residents expect their energy costs to plummet. 

The truth is that having a solar system installed does not come without its challenges. To reap the benefits of your solar energy investment and attain the amount of savings you were hoping for, it is crucial to understand the reasons behind the high energy costs. 

Knowing How Your Solar Energy System Works

System Size vs. Energy Consumption Mismatch

Under-charging installation is one of the major reasons your electricity consumption is still high. Most homeowners fail to account for their actual energy consumption during the planning phase of their renewable energy setup. For example, a 5kW system may look good on paper, but households that come with multiple air conditioners, pool pumps, and EV charging stations will need significantly larger installations.

Renewable energy pros solar panel installation Sunshine Coast firms like Ahlec Solar make it a practice to perform energy audits before making a recommendation for system sizes. These assessments look into your usage history, future energy requirements, and roof space to make sure it is well optimised. 

Timing Of Energy Usage Patterns 

As with any Solar power Sunshine Coast system, energy is produced from 6 AM to 6 PM, with the system fully functional between the set hours. Households tend to consume the highest portion of energy from around the 5 PM mark as families come home for the day, prepare dinner, and wind down with the TV for the evening. Unfortunately, this coincides with the, ‘Use it or lose it,’ mentality for energy consumers. 

Consider the following:

• Air conditioning and Heating equipment

• Electric cooking appliances

• Water heating

• Entertainment systems and Lighting

• Clothes washers and dryers

Factors influencing the performance of solar energy systems

Shading and Orientation Problems 

An issue that is very common, Shading Problems, can cause a very noticeable effect on the system's efficiency for the output. The way solar panels are normally linked means that any morning shadows from neighbouring buildings, trees, or other structures can greatly reduce output for the remainder of the day.

Sunshine Coast solar installations must consider:  

• Nearby vegetation growth over time  

• Construction development  

• Roof pitch and azimuth  

• Seasonal sun path fluctuations  

Decommissioning and Servicing  

Solar panels naturally degrade over time, and their efficiency wanes due to Australian dust, bird droppings, and severe weather. Without proper maintenance and cleaning, panels lose 0.5-0.8% efficiency every year.  

Warning signs your system needs maintenance:  

• Accumulated dirt and debris  

• Overshadowing or damaged panels  

• Panel and inverter error messages  

• Performance monitoring system flags  

• Performance drops  

Grid Connection and Billing Complications  

Feed-in vs. Tariff Rates for Electricity  

Queensland feed-in tariffs are between 3-10 cents per kilowatt hour. In contrast, purchasing power from the grid costs 25-35 cents. Each exported unit earned is far less than the imported energy.  

Time-of-Use Pricing  

Electricity retailers have adopted time-of-use pricing, where electricity costs vary at different times of the day. The highest rates fall between 4 PM to 9 PM, which is when most solar systems Sunshine Coast are set to deliver their minimal energy output.

Knowing how your bills are calculated can assist with improving your energy use. If your everyday jobs consume a lot of energy, try scheduling them for the daytime when your solar panels are producing electricity. 

Seasonal and Weather Differences

Reduced Solar Production in Winter

The lower angles of the sun and shorter days that come with the winter months in Australia result in significantly lower solar generation. Locals from the Sunshine Coast are likely to see a decline of around 40 to 50 per cent in production during the June-July winter months, when compared to the peak summer months. This means that winter electricity bills are likely to be higher than normal, and that systems are operating as expected.

Weather Influence

Daily energy production can be negatively impacted by storms, prolonged cloudy periods, and other atmospheric happenings. Weather patterns such as La Niña and El Niño can affect the conditions for months and, in return, impact how the system performs and the electricity fees. 

Energy Storage Options

Failure to Provide Energy Storage Options

In the absence of energy storage, excess solar production gets exported to the grid during the daytime at lower feed-in rates. Grid electricity is expensive during evening hours, and having to purchase it can be a burden. Battery systems help to ease this burden as they allow surplus generation to be captured during the day and stored for evening use, improving self-consumption and decreasing reliance on grid electricity.

Today’s lithium battery systems come with:

• A warranty of 10-15 years

• Automated Energy regulation

• Provide backup power during outages

• Improved return on investment

Battery System Sizing

An undersized battery will capture insufficient surplus energy, while oversized systems will result in unnecessary expenses. Expert solar consultants on the Sunshine Coast will ensure optimal battery sizing and solar output by closely assessing the energy and solar generation usage patterns. 

Appliance Efficiency and Energy Usage Habits

Energy-Intensive Appliances

Older appliances also negate the benefits gained through solar energy. Devices like electric hot water systems, older air conditioners, and inefficient pool pumps are outdated and consume a lot of energy.

Consider upgrading to:

• Heat pump hot water systems  

• Inverter air conditioning units  

• Variable speed pool pumps  

• LED lights throughout your house  

• Kitchen appliances that are energy-efficient  

Managing Energy Use in the Household    

Changing some simple habits can increase your return on investment when it comes to solar:

• Run dishwashers and washing machines during the sunniest hours  

• Use timers for pool pumps to charge during peak hours  

• Preheat or precool your house during solar production hours  

• Charge electric vehicles during the day  

Monitoring the System and Detecting Faults  

Why Monitoring Performance is Important  

Many homeowners never check their systems to see how they are performing, missing out on very critical faults or faults and degradation. Today, most systems can be monitored to provide real-time generation data, assisting a homeowner in identifying issues without delay.  

Key monitoring metrics include:  

• Daily energy production  

• System efficiency ratings  

• Performance of each panel  

• Alerts and status of the inverter  

• Performance comparisons over time  

Common System Faults  

Sunshine Coast solar systems can have several technical faults:  

• Malfunctions and failures of the inverters  

• Problems with the DC isolators  

• Issues with the wiring or connections  

• Weather-related panel damage  

• Issues with grid connections  

By having regular professional inspections, these issues can be identified and corrected before they adversely affect performance.

Expert Assistance from Ahlec Solar 

Thorough System Evaluation 

Ahlec Solar’s assessed specialists focus on evaluating and diagnosing implemented systems to streamline workflows and pinpoint optimisation areas. They evaluate technical and operational benchmarks as well as check for any necessary updates on the systems in place. 

Tailored Adjustment Solutions 

Depending on specific needs, Ahlec Solar suggests the following actions to assist customers:

• Expand systems for added efficiency 

• Incorporate battery storage 

• Implement advanced energy management software 

• Upgrade appliances 

• Optimise energy usage strategies 

Financial Aspects and The Return on Investment 

The Payback Period 

Achievable targets require focus on the following areas:

• Savings from projected energy use 

• System upkeep expenses 

• Energy cost escalation for electricity 

• System replacement timeframes 

• Changes in subsidies and incentives from the government 

Investment Return 

Adequate direction from leading firms, like Ahlec Solar, guarantees the desired results from the renewable energy initiatives, as they understand local policies and regulatory frameworks, together with system design. 

Consideration: Taking Steps for Better Outcomes 

Soaring electricity expenses, even with solar panel installations, can be a result of undersizing the systems, low technical performance, poor user engagement, and the billing framework. Understanding these factors enables one to better strategise to fully leverage the renewable energy system they have put in place.

If your solar installation is incurring continuous elevated electricity expenses, it may be worth arranging for a professional evaluation. Ahlec Solar, for instance, has the right experience to pinpoint exact problems and offer solutions that are not expensive.

Like any other technology, solar energy systems need continuous fine-tuning and a few modifications to perform at their peak. Optimising your photovoltaic investment with professional guidance can ensure that it brings about significant savings in electricity costs for years.